docs(W4): document contract — stamp kind and status on 104 live docs (#1350)

Co-authored-by: veronica <[email protected]>

docs/README.md

@@ -1,3 +1,9 @@
+---
+kind: spec
+source_of_truth: true
+status: active
+---
+
 # Mosaic Stack Documentation
 
 This directory is the canonical home for Mosaic Stack product, architecture, API, operations, and delivery documentation.
@@ -146,21 +152,51 @@ Every canonical page should:
 7. Include an owner or maintenance responsibility for operationally sensitive content.
 8. Link to the relevant book index and related canonical pages.
 
-Recommended front matter for canonical pages:
+Required front matter for every canonical page:
 
 ```yaml
 ---
-title: Human-readable page title
-type: guide
-audience: developer
-status: current
-source_of_truth: false
+kind: tracking | projection | spec | guide | record | superseded
+status: active # or: completed | superseded-by: <path>
+source_of_truth: false # optional, defaults false
+audience: developer # optional: user | admin | developer | all
+title: Human-readable page title # optional
 ---
 ```
 
-Allowed `type` values include `guide`, `concept`, `reference`, `decision`, `rfc`, and `runbook`. Allowed `audience` values are `user`, `admin`, `developer`, and `all`. Allowed `status` values are `current`, `draft`, `deprecated`, and `historical`.
+`kind` says what the document **is**. One value, required, and it follows the document's content,
+never its filename: a file named `TASKS.md` whose body says "this is a build plan, not a task
+tracker" is a `spec`.
 
-Indexes may omit front matter when their purpose is self-evident. A page with normative authority must explicitly identify the authority it owns and the boundaries of that authority.
+| kind       | rule                                                             |
+| ---------- | ---------------------------------------------------------------- |
+| tracking   | Live state, single-writer. Never a spec                          |
+| projection | Generated. Never hand-edited. MUST have a drift test             |
+| spec       | How to build one goal or workstream                              |
+| guide      | Explains use. Decides nothing                                    |
+| record     | What happened. Never authoritative, never updated after the fact |
+| superseded | Kept for history, and NAMES its replacement                      |
+
+`source_of_truth` is a separate boolean because authority is **orthogonal to kind**. A document can
+be a `spec` and still be the thing everything else answers to;
+`docs/requirements/native-kanban-sot.md` is exactly that. Folding authority into `kind` forced one
+field to carry two independent facts, which is why an earlier draft of this contract could not
+classify that file at all.
+
+`status` has three values. `active` means in force. `completed` means the work the document
+describes landed and the document is now finished rather than stale; executed implementation plans
+take this. `superseded-by: <path>` replaces `status` entirely and names the replacement.
+
+**This contract covers `.md` files only.** It is not an omission: a YAML document cannot carry YAML
+front matter. The repository's own `[email protected]` throws `Source contains multiple documents` on a
+front-mattered `.yaml`, and `parseNorthStar` (`packages/mosaic/src/commands/fleet.ts:242`) is a live
+consumer that would break. `.yaml` sources declare their own kind inside the document or not at all.
+
+A `parent` field is planned and is deliberately not yet required; it lands once the docs flatten
+settles the paths it would point at.
+
+Indexes may omit front matter when their purpose is self-evident. A page with normative authority
+must explicitly identify the authority it owns and the boundaries of that authority.
 
 ## Obsidian and link conventions