Add the content service and MCP server (phase 2)

services/content watches the vault's Site folder, runs every change through
fixed rules, keeps the last accepted version of each note with its history,
and serves one write API. The HTTP API, the MCP server for agents, and the
admin page and editing tools to come all write through it.

- SQLite store with history, review queue, redirects, links and full-text search
- Rules: invalid, misplaced, duplicate name or slug, text loss, secrets,
  agent contact details, agent edits, agent publishing, agent batches
- Watcher with debounce and a periodic full scan
- HTTP API with reader, agent, editor and admin tokens
- MCP tools: search, get_note, get_schema, list_held, set_status,
  add_library_item, update_fields, draft_post
- Tests, including taking in all 545 migrated notes with nothing held

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_012aSbo2D1qP8cMFQCykf7kx

README.md

@@ -12,12 +12,12 @@ with the decisions behind it, is the
 | --- | --- |
 | `packages/schema` | The one definition of every note type: fields, folders, file names, and the checks for one note and for the whole folder. The migration, the content service, the MCP server, the site and any later editing tool all use it. |
 | `vault-kit` | What goes into the vault: the Obsidian templates (generated from the schema) and the Site guide. |
+| `services/content` | The content service: watches the Site folder, runs the rules, keeps the last good version and its history, and serves the one write API. The MCP server for agents is part of it. See [docs/content-service.md](docs/content-service.md). |
 | `tools/migrate` | The one-time migration from the old site's data into Site folder notes. |
 | `docs` | How the pieces fit. Start with [docs/content-model.md](docs/content-model.md). |
 | `legacy` | The old site, kept for reference only. Nothing outside it imports from it except the migration. |
 
-Coming in later phases: `services/content` (the content service and its MCP
-server), the admin page, and the new site.
+Coming in later phases: the admin page, the component library, and the new site.
 
 ## Commands
 
@@ -29,6 +29,10 @@ npm run check      # typecheck and tests
 npm run migrate    # writes out/24.01_PersonalWebsite and out/MIGRATION-REPORT.md
 npm run templates  # regenerates vault-kit templates after a schema change
 npm run schema:json  # writes a JSON Schema per note type to packages/schema/json/
+
+# the content service, against a copy of the Site folder
+SITE_DIR=out/24.01_PersonalWebsite/Site DATA_DIR=data \
+CONTENT_TOKENS="reader:<24+ chars>,admin:<24+ chars>" npm run content
 ```
 
 ## The old site