chore(git-sync): remove dead Settings REST fields, warn on inert REMOTE_TEMPLATE, fix stale docstrings (review)

Dead code / doc-vs-code cleanup from review #4404:
- Drop the unused Settings.docmostApiUrl/Email/Password fields (the native
  in-process datasource never reads them; the engine only used docmostSpaceId).
  Removed from the type, buildSettings, and the 4 engine test suites that
  fabricated them.
- Warn ONCE at startup when GIT_SYNC_REMOTE_TEMPLATE is set — remote push is
  deferred (SPEC §7) so the value is currently inert; the operator now gets a
  log line instead of a silent no-op.
- Correct stale docstrings that claimed live-destructive code was 'FAKES only /
  NEXT increment / no live wiring' (applyPushActions runs LIVE via
  runCycle->orchestrator); that importPageMarkdown receives a 'self-contained
  file (meta+body)' (it receives the stripped body); and that the Yjs body merge
  is '2-way' (3-way runs end-to-end when the base is present).

No behavior change (except the new warning); build + git-sync smoke verified.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

packages/git-sync/src/engine/client.types.ts

@@ -70,14 +70,16 @@ export interface GitSyncClient {
   // --- writes (push) --------------------------------------------------------
 
   /**
-   * Merge a page's body from a self-contained markdown file (meta + body). The
-   * collab/Yjs write path (SPEC §2/§15.6) — never a raw jsonb overwrite.
-   * `applyPushActions` reads only an optional `updatedAt` off the result
-   * (via `extractUpdatedAt`, tolerant of extra fields).
+   * Merge a page's markdown BODY into the live page. `applyPushActions` passes
+   * the file's body with the frontmatter AND any git conflict markers already
+   * stripped — NOT the raw self-contained file — so `fullMarkdown` here is clean
+   * body text (the datasource re-parses defensively). The collab/Yjs write path
+   * (SPEC §2/§15.6) — never a raw jsonb overwrite. `applyPushActions` reads only
+   * an optional `updatedAt` off the result (via `extractUpdatedAt`).
    *
-   * `baseMarkdown` is the last-synced version of the file (`refs/docmost/
-   * last-pushed`), the common ancestor for a THREE-WAY merge against the live
-   * doc so concurrent human edits survive (review #5). Optional/null -> 2-way.
+   * `baseMarkdown` is the last-synced body (from `refs/docmost/last-pushed`,
+   * likewise stripped), the common ancestor for a THREE-WAY merge against the
+   * live doc so concurrent human edits survive (review #5). Optional/null -> 2-way.
    */
   importPageMarkdown(
     pageId: string,

packages/git-sync/src/engine/push.ts

@@ -486,9 +486,10 @@ export const LAST_PUSHED_REF = "refs/docmost/last-pushed";
 export const DOCMOST_BRANCH = "docmost";
 
 /**
- * Injectable IO for `applyPushActions`. The real `main` (NEXT increment) wires
- * these to the live client, `node:fs/promises`, and the vault git wrapper; this
- * increment drives them only through FAKES in tests (no live destructive run).
+ * Injectable IO for `applyPushActions`. In production these are wired to the live
+ * client (the native GitmostDataSource), `node:fs/promises`, and the vault git
+ * wrapper — `applyPushActions` runs LIVE via runPush -> runCycle -> the
+ * orchestrator's driveCycle. Tests substitute FAKES through the same seam.
  *   - `client`: the create/update/delete/move/rename subset of `GitSyncClient`.
  *   - `readFile`/`writeFile`: read a changed file's body / write a file back
  *     (by vault-relative path; the applier does not resolve absolute paths so
@@ -645,13 +646,13 @@ export interface ApplyPushResult {
 }
 
 /**
- * THIN IO applier for the COMMON push cases (create/update/delete). Exercised
- * via FAKES only in this increment — there is no live wiring.
+ * THIN IO applier for the COMMON push cases (create/update/delete). Runs LIVE in
+ * production (via runPush -> runCycle -> orchestrator); tests drive it with FAKES.
  *
  *   - UPDATE: read the file body, then `client.importPageMarkdown(pageId, body)`.
  *     This is the collab/Yjs write path (SPEC §2/§15.6) — NEVER a raw jsonb
- *     overwrite. The full self-contained markdown (meta + body) is sent as-is;
- *     `importPageMarkdown` parses the meta/body itself.
+ *     overwrite. The file's markdown is sent as-is; `importPageMarkdown` parses
+ *     the meta/body itself.
  *   - CREATE: derive title/spaceId/parentPageId from the file's current meta,
  *     `client.createPage(...)`, take the assigned pageId from the result, and
  *     write it BACK as the file's `gitmost_id` frontmatter (re-serialized via
@@ -1379,8 +1380,8 @@ function extractUpdatedAt(result: unknown): { updatedAt?: string } {
 // Docmost writes, NO ref advance); an explicit `--apply` is the ONLY path that
 // builds a client and mutates Docmost.
 //
-// Every external effect is injected (`PushDeps`) so the whole orchestration is
-// driven by FAKES in tests — no live Docmost, git, fs, or network.
+// Every external effect is injected (`PushDeps`): production wires the live
+// Docmost client, git, and fs; tests substitute FAKES through the same seam.
 
 /**
  * The human ("local") git identity used for engine-made commits on `main` in the

packages/git-sync/src/engine/settings.ts

@@ -8,9 +8,6 @@
  */
 
 export type Settings = {
-  docmostApiUrl: string;
-  docmostEmail: string;
-  docmostPassword: string;
   docmostSpaceId: string;
   vaultPath: string;
   gitRemote?: string;