feat: Add @mosaic/cli-tools package for git operations

New package providing CLI tools that work with both Gitea and GitHub:

Commands:
- mosaic-issue-{create,list,view,assign,edit,close,reopen,comment}
- mosaic-pr-{create,list,view,merge,review,close}
- mosaic-milestone-{create,list,close}

Features:
- Auto-detects platform (Gitea vs GitHub) from git remote
- Unified interface regardless of platform
- Available via `pnpm exec mosaic-*` in monorepo context

Updated docs/claude/orchestrator.md:
- Added CLI Tools section with usage examples
- Updated issue creation to use package commands

This makes Mosaic Stack fully self-contained for orchestration tooling.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

packages/cli-tools/bin/issue-assign.sh

@@ -0,0 +1,135 @@
+#!/bin/bash
+# issue-assign.sh - Assign issues on Gitea or GitHub
+# Usage: issue-assign.sh -i ISSUE_NUMBER [-a assignee] [-l labels] [-m milestone]
+
+set -e
+
+SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+source "$SCRIPT_DIR/detect-platform.sh"
+
+# Default values
+ISSUE=""
+ASSIGNEE=""
+LABELS=""
+MILESTONE=""
+REMOVE_ASSIGNEE=false
+
+usage() {
+    cat <<EOF
+Usage: $(basename "$0") [OPTIONS]
+
+Assign or update an issue on the current repository (Gitea or GitHub).
+
+Options:
+    -i, --issue NUMBER      Issue number (required)
+    -a, --assignee USER     Assign to user (use @me for self)
+    -l, --labels LABELS     Add comma-separated labels
+    -m, --milestone NAME    Set milestone
+    -r, --remove-assignee   Remove current assignee
+    -h, --help              Show this help message
+
+Examples:
+    $(basename "$0") -i 42 -a "username"
+    $(basename "$0") -i 42 -l "in-progress" -m "0.2.0"
+    $(basename "$0") -i 42 -a @me
+EOF
+    exit 1
+}
+
+# Parse arguments
+while [[ $# -gt 0 ]]; do
+    case $1 in
+        -i|--issue)
+            ISSUE="$2"
+            shift 2
+            ;;
+        -a|--assignee)
+            ASSIGNEE="$2"
+            shift 2
+            ;;
+        -l|--labels)
+            LABELS="$2"
+            shift 2
+            ;;
+        -m|--milestone)
+            MILESTONE="$2"
+            shift 2
+            ;;
+        -r|--remove-assignee)
+            REMOVE_ASSIGNEE=true
+            shift
+            ;;
+        -h|--help)
+            usage
+            ;;
+        *)
+            echo "Unknown option: $1" >&2
+            usage
+            ;;
+    esac
+done
+
+if [[ -z "$ISSUE" ]]; then
+    echo "Error: Issue number is required (-i)" >&2
+    usage
+fi
+
+PLATFORM=$(detect_platform)
+
+case "$PLATFORM" in
+    github)
+        if [[ -n "$ASSIGNEE" ]]; then
+            gh issue edit "$ISSUE" --add-assignee "$ASSIGNEE"
+        fi
+        if [[ "$REMOVE_ASSIGNEE" == true ]]; then
+            # Get current assignees and remove them
+            CURRENT=$(gh issue view "$ISSUE" --json assignees -q '.assignees[].login' 2>/dev/null | tr '\n' ',')
+            if [[ -n "$CURRENT" ]]; then
+                gh issue edit "$ISSUE" --remove-assignee "${CURRENT%,}"
+            fi
+        fi
+        if [[ -n "$LABELS" ]]; then
+            gh issue edit "$ISSUE" --add-label "$LABELS"
+        fi
+        if [[ -n "$MILESTONE" ]]; then
+            gh issue edit "$ISSUE" --milestone "$MILESTONE"
+        fi
+        echo "Issue #$ISSUE updated successfully"
+        ;;
+    gitea)
+        # tea issue edit syntax
+        CMD="tea issue edit $ISSUE"
+        NEEDS_EDIT=false
+
+        if [[ -n "$ASSIGNEE" ]]; then
+            # tea uses --assignees flag
+            CMD="$CMD --assignees \"$ASSIGNEE\""
+            NEEDS_EDIT=true
+        fi
+        if [[ -n "$LABELS" ]]; then
+            # tea uses --labels flag (replaces existing)
+            CMD="$CMD --labels \"$LABELS\""
+            NEEDS_EDIT=true
+        fi
+        if [[ -n "$MILESTONE" ]]; then
+            MILESTONE_ID=$(tea milestones list 2>/dev/null | grep -E "^\s*[0-9]+" | grep "$MILESTONE" | awk '{print $1}' | head -1)
+            if [[ -n "$MILESTONE_ID" ]]; then
+                CMD="$CMD --milestone $MILESTONE_ID"
+                NEEDS_EDIT=true
+            else
+                echo "Warning: Could not find milestone '$MILESTONE'" >&2
+            fi
+        fi
+
+        if [[ "$NEEDS_EDIT" == true ]]; then
+            eval "$CMD"
+            echo "Issue #$ISSUE updated successfully"
+        else
+            echo "No changes specified"
+        fi
+        ;;
+    *)
+        echo "Error: Could not detect git platform" >&2
+        exit 1
+        ;;
+esac