feat(#82): implement Personality Module

- Add Personality model to Prisma schema with FormalityLevel enum
- Create migration and seed with 6 default personalities
- Implement CRUD API with TDD approach (97.67% coverage)
  * PersonalitiesService: findAll, findOne, findDefault, create, update, remove
  * PersonalitiesController: REST endpoints with auth guards
  * Comprehensive test coverage (21 passing tests)
- Add Personality types to shared package
- Create frontend components:
  * PersonalitySelector: dropdown for choosing personality
  * PersonalityPreview: preview personality style and system prompt
  * PersonalityForm: create/edit personalities with validation
  * Settings page: manage personalities with CRUD operations
- Integrate with Ollama API:
  * Support personalityId in chat endpoint
  * Auto-inject system prompt from personality
  * Fall back to default personality if not specified
- API client for frontend personality management

All tests passing with 97.67% backend coverage (exceeds 85% requirement)

apps/api/src/common/dto/base-filter.dto.spec.ts

@@ -0,0 +1,170 @@
+import { describe, expect, it } from "vitest";
+import { validate } from "class-validator";
+import { plainToClass } from "class-transformer";
+import { BaseFilterDto, BasePaginationDto, SortOrder } from "./base-filter.dto";
+
+describe("BasePaginationDto", () => {
+  it("should accept valid pagination parameters", async () => {
+    const dto = plainToClass(BasePaginationDto, {
+      page: 1,
+      limit: 20,
+    });
+
+    const errors = await validate(dto);
+    expect(errors.length).toBe(0);
+    expect(dto.page).toBe(1);
+    expect(dto.limit).toBe(20);
+  });
+
+  it("should use default values when not provided", async () => {
+    const dto = plainToClass(BasePaginationDto, {});
+
+    const errors = await validate(dto);
+    expect(errors.length).toBe(0);
+  });
+
+  it("should reject page less than 1", async () => {
+    const dto = plainToClass(BasePaginationDto, {
+      page: 0,
+    });
+
+    const errors = await validate(dto);
+    expect(errors.length).toBeGreaterThan(0);
+    expect(errors[0].property).toBe("page");
+  });
+
+  it("should reject limit less than 1", async () => {
+    const dto = plainToClass(BasePaginationDto, {
+      limit: 0,
+    });
+
+    const errors = await validate(dto);
+    expect(errors.length).toBeGreaterThan(0);
+    expect(errors[0].property).toBe("limit");
+  });
+
+  it("should reject limit greater than 100", async () => {
+    const dto = plainToClass(BasePaginationDto, {
+      limit: 101,
+    });
+
+    const errors = await validate(dto);
+    expect(errors.length).toBeGreaterThan(0);
+    expect(errors[0].property).toBe("limit");
+  });
+
+  it("should transform string numbers to integers", async () => {
+    const dto = plainToClass(BasePaginationDto, {
+      page: "2" as any,
+      limit: "30" as any,
+    });
+
+    const errors = await validate(dto);
+    expect(errors.length).toBe(0);
+    expect(dto.page).toBe(2);
+    expect(dto.limit).toBe(30);
+  });
+});
+
+describe("BaseFilterDto", () => {
+  it("should accept valid search parameter", async () => {
+    const dto = plainToClass(BaseFilterDto, {
+      search: "test query",
+    });
+
+    const errors = await validate(dto);
+    expect(errors.length).toBe(0);
+    expect(dto.search).toBe("test query");
+  });
+
+  it("should accept valid sortBy parameter", async () => {
+    const dto = plainToClass(BaseFilterDto, {
+      sortBy: "createdAt",
+    });
+
+    const errors = await validate(dto);
+    expect(errors.length).toBe(0);
+    expect(dto.sortBy).toBe("createdAt");
+  });
+
+  it("should accept valid sortOrder parameter", async () => {
+    const dto = plainToClass(BaseFilterDto, {
+      sortOrder: SortOrder.DESC,
+    });
+
+    const errors = await validate(dto);
+    expect(errors.length).toBe(0);
+    expect(dto.sortOrder).toBe(SortOrder.DESC);
+  });
+
+  it("should reject invalid sortOrder", async () => {
+    const dto = plainToClass(BaseFilterDto, {
+      sortOrder: "invalid" as any,
+    });
+
+    const errors = await validate(dto);
+    expect(errors.length).toBeGreaterThan(0);
+    expect(errors.some(e => e.property === "sortOrder")).toBe(true);
+  });
+
+  it("should accept comma-separated sortBy fields", async () => {
+    const dto = plainToClass(BaseFilterDto, {
+      sortBy: "priority,createdAt",
+    });
+
+    const errors = await validate(dto);
+    expect(errors.length).toBe(0);
+    expect(dto.sortBy).toBe("priority,createdAt");
+  });
+
+  it("should accept date range filters", async () => {
+    const dto = plainToClass(BaseFilterDto, {
+      dateFrom: "2024-01-01T00:00:00Z",
+      dateTo: "2024-12-31T23:59:59Z",
+    });
+
+    const errors = await validate(dto);
+    expect(errors.length).toBe(0);
+  });
+
+  it("should reject invalid date format for dateFrom", async () => {
+    const dto = plainToClass(BaseFilterDto, {
+      dateFrom: "not-a-date",
+    });
+
+    const errors = await validate(dto);
+    expect(errors.length).toBeGreaterThan(0);
+    expect(errors.some(e => e.property === "dateFrom")).toBe(true);
+  });
+
+  it("should reject invalid date format for dateTo", async () => {
+    const dto = plainToClass(BaseFilterDto, {
+      dateTo: "not-a-date",
+    });
+
+    const errors = await validate(dto);
+    expect(errors.length).toBeGreaterThan(0);
+    expect(errors.some(e => e.property === "dateTo")).toBe(true);
+  });
+
+  it("should trim whitespace from search query", async () => {
+    const dto = plainToClass(BaseFilterDto, {
+      search: "  test query  ",
+    });
+
+    const errors = await validate(dto);
+    expect(errors.length).toBe(0);
+    expect(dto.search).toBe("test query");
+  });
+
+  it("should reject search queries longer than 500 characters", async () => {
+    const longString = "a".repeat(501);
+    const dto = plainToClass(BaseFilterDto, {
+      search: longString,
+    });
+
+    const errors = await validate(dto);
+    expect(errors.length).toBeGreaterThan(0);
+    expect(errors.some(e => e.property === "search")).toBe(true);
+  });
+});

apps/api/src/common/dto/base-filter.dto.ts

@@ -0,0 +1,82 @@
+import {
+  IsOptional,
+  IsInt,
+  Min,
+  Max,
+  IsString,
+  IsEnum,
+  IsDateString,
+  MaxLength,
+} from "class-validator";
+import { Type, Transform } from "class-transformer";
+
+/**
+ * Enum for sort order
+ */
+export enum SortOrder {
+  ASC = "asc",
+  DESC = "desc",
+}
+
+/**
+ * Base DTO for pagination
+ */
+export class BasePaginationDto {
+  @IsOptional()
+  @Type(() => Number)
+  @IsInt({ message: "page must be an integer" })
+  @Min(1, { message: "page must be at least 1" })
+  page?: number = 1;
+
+  @IsOptional()
+  @Type(() => Number)
+  @IsInt({ message: "limit must be an integer" })
+  @Min(1, { message: "limit must be at least 1" })
+  @Max(100, { message: "limit must not exceed 100" })
+  limit?: number = 50;
+}
+
+/**
+ * Base DTO for filtering and sorting
+ * Provides common filtering capabilities across all entities
+ */
+export class BaseFilterDto extends BasePaginationDto {
+  /**
+   * Full-text search query
+   * Searches across title, description, and other text fields
+   */
+  @IsOptional()
+  @IsString({ message: "search must be a string" })
+  @MaxLength(500, { message: "search must not exceed 500 characters" })
+  @Transform(({ value }) => (typeof value === "string" ? value.trim() : value))
+  search?: string;
+
+  /**
+   * Field(s) to sort by
+   * Can be comma-separated for multi-field sorting (e.g., "priority,createdAt")
+   */
+  @IsOptional()
+  @IsString({ message: "sortBy must be a string" })
+  sortBy?: string;
+
+  /**
+   * Sort order (ascending or descending)
+   */
+  @IsOptional()
+  @IsEnum(SortOrder, { message: "sortOrder must be either 'asc' or 'desc'" })
+  sortOrder?: SortOrder = SortOrder.DESC;
+
+  /**
+   * Filter by date range - start date
+   */
+  @IsOptional()
+  @IsDateString({}, { message: "dateFrom must be a valid ISO 8601 date string" })
+  dateFrom?: Date;
+
+  /**
+   * Filter by date range - end date
+   */
+  @IsOptional()
+  @IsDateString({}, { message: "dateTo must be a valid ISO 8601 date string" })
+  dateTo?: Date;
+}

apps/api/src/common/dto/index.ts

@@ -0,0 +1 @@
+export * from "./base-filter.dto";