feat(update): stash/restore by default + settable discard for non-interactive updates (reverts #38542, #39568) (#39645)

* Revert "fix(update): require managed marker before destructive clean"

This reverts commit c8e80cd0bf.

* Revert "fix(update): stop stash/restore from clobbering desktop source on managed clones (#38542)"

This reverts commit 8a19884bf3.

* chore(install): keep npm ci desktop-build fix after stash revert

The destructive-clean reverts (#38542/#39568) pulled the desktop
workspace install back to bare `npm install`. The npm ci -> npm install
fallback is orthogonal build-correctness (avoids the Windows
workspace-hoisting flake where install reports up-to-date against a
stale marker while node_modules is empty, breaking tsc -b). Preserve it.

* feat(update): settable stash-or-discard for non-interactive local changes

Adds updates.non_interactive_local_changes (stash | discard, default
stash). Governs ONLY non-interactive updates (desktop/chat app, gateway,
--yes) — interactive terminal updates always stash-and-ask, unchanged.

- config.py: new key under existing updates section; _config_version 26->27.
- main.py: _cmd_update_impl detects non-interactive (gateway/--yes/no-TTY),
  reads the setting; new _discard_stashed_changes() drops the stash
  (stash-and-drop, never reset --hard/clean -fd, so ignored paths survive).
  Post-pull restore site branches on it; the bail-out and up-to-date
  restores always preserve work.
- web_server.py + apps/desktop settings: exposes it as a stash/discard
  select (Advanced section, In-App Update Local Changes).
- docs + tests (discard drops, stash restores, interactive ignores setting,
  missing section defaults to stash).

* fix(install.ps1): stash/restore instead of reset --hard on Windows update

The PR reverted the destructive update path to stash/restore everywhere
except scripts/install.ps1, whose managed-clone update path still ran
`git reset --hard HEAD` before checkout — silently destroying agent-edited
tracked source on Windows (the same #38542 data-loss class the PR fixes).

- Replace `git reset --hard HEAD` with stash-before-checkout +
  restore-after-checkout, mirroring install.sh. Untracked files are
  included so agent-created dirs (e.g. tinker-atropos/) survive.
- Keep `core.autocrlf false` (it prevents the phantom CRLF dirt that made
  the stash necessary; it's also load-bearing for a clean restore).
- Wrap all three checkout modes (Commit/Tag/Branch); Branch case now uses
  `git pull --ff-only` so local commits are never clobbered.
- Only prompt to restore when a real console is attached (UserInteractive
  + non-redirected stdin/stdout + ConsoleHost); the desktop Update button
  and bootstrap have no usable console, so they default to restore and
  never hang on Read-Host.
- On restore conflict or a failed update, the stash is preserved with
  recovery instructions — work is never silently dropped.

Validated on Windows (PowerShell 5.1, git 2.54): AST parse clean;
E2E non-conflicting restore applies+drops cleanly with ignored paths
(node_modules) untouched; conflicting restore preserves the stash.

---------

Co-authored-by: alt-glitch <balyan.sid@gmail.com>

hermes_cli/web_server.py

@@ -439,6 +439,16 @@ _SCHEMA_OVERRIDES: Dict[str, Dict[str, Any]] = {
         "description": "Reasoning effort for delegated subagents",
         "options": ["", "low", "medium", "high"],
     },
+    "updates.non_interactive_local_changes": {
+        "type": "select",
+        "description": (
+            "When the chat app / gateway updates Hermes (no terminal prompt), "
+            "what to do with uncommitted local source edits. 'stash' keeps them "
+            "and re-applies them after the update; 'discard' throws them away. "
+            "Terminal updates always ask, regardless of this setting."
+        ),
+        "options": ["stash", "discard"],
+    },
 }
 
 # Categories with fewer fields get merged into "general" to avoid tab sprawl.
@@ -455,6 +465,7 @@ _CATEGORY_MERGE: Dict[str, str] = {
     "code_execution": "agent",
     "prompt_caching": "agent",
     "goals": "agent",
+    "updates": "general",
     # Only `telegram.reactions` currently lives under telegram — fold it in
     # with the other messaging-platform config (discord) so it isn't an
     # orphan tab of one field.