M2 audit: excise managed connectors and xAI media-gen tools

Managed connectors (grok.com MCP admin) removed root-and-branch:
- The managed-MCP fetch/injection pipeline is gone, including the whole
  kigi-shell-session-support crate (managed-config fetch client, gateway
  tool catalog + dispatch, header injection, refresh task), reactive
  managed re-auth, mcp_doctor's grok.com-source discovery, and the
  [managed_mcps] config surface.
- TUI: the 'Managed by grok.com' section, connectors URL/deep-link,
  Action::OpenManagedConnectors, and session_team_id are gone. Local MCP
  management (list/toggle/add/remove/auth/tools) is fully intact.
- Kept as LOCAL policy: managed-settings.json MCP allow/deny enforcement,
  the multi-source local MCP merge, folder-trust gating. PluginOrigin
  Project/User labels kept (they tag locally discovered plugin dirs).

imagine/media-gen tools (xAI image/video generation) removed:
- image_gen, image_edit, video_gen, image_to_video, reference_to_video
  implementations, registrations, ToolKind/ToolInput/Output variants
  (serde-safe), config plumbing end to end, ZDR video machinery,
  /imagine + /imagine-video commands and guidance text, the bundled
  imagine skill (added to legacy cleanup so user installs delete it),
  and the media-gen render path.
- Kept: image INPUT (paste/attach, [Image #N] meta, pdf/image fetch,
  clipboard wrap), generic media-ref rendering, and the generic tool
  401-retry machinery (tests renamed, assertions unweakened).
- deploy_app stays: it is a permanently-disabled local stub deploying
  nowhere.

121 files changed, 8 deleted. Gates: workspace check/clippy 0/0, fmt,
deny ok; suites green (tools 2554, shell 4862, tui 6608, workspace
1042). Remaining grok.com strings live only in the auth-method ids and
changelog archives (§9/M3 sweep).

crates/codegen/kigi-pager-render/src/render/osc8.rs

@@ -254,7 +254,7 @@ struct RowSegment {
 /// joiner to the *previous* row (see `BlockLine::joiner`): `None` = hard
 /// break, `Some("")` = mid-word wrap, `Some(" ")` = word wrap. Consecutive
 /// rows connected by `Some(..)` joiners are re-joined into one logical line
-/// before matching, so a long path or URL soft-wrapped across rows (imagine
+/// before matching, so a long path or URL soft-wrapped across rows (media
 /// media lives at `~/.kigi/sessions/%2F…/images/1.jpg`, which wraps in
 /// narrow panes) is detected whole and each row's fragment gets its own
 /// clickable overlay region. Spans within a row are likewise concatenated so
@@ -858,7 +858,7 @@ mod tests {
     #[test]
     fn scan_detects_grok_session_media_path() {
         // Dot-directory (`.kigi`), percent-encoded session segment, and a
-        // trailing sentence period — the shape of `image_gen` output prose.
+        // trailing sentence period — the shape of media-tool output prose.
         let line = make_line("Saved to /Users/alice/.kigi/sessions/%2Fabc/00000000/images/1.jpg.");
         let mut overlay = LinkOverlay::new();
         scan_unjoined(std::iter::once((0, &line)), 0, &[], &mut overlay);
@@ -873,7 +873,7 @@ mod tests {
 
     #[test]
     fn scan_detects_media_path_soft_wrapped_across_rows() {
-        // Regression: `image_gen` output prose wraps the long session path
+        // Regression: media-tool output prose wraps the long session path
         // across visual rows (`joiner: Some("")` mid-word break). Previously
         // each row was scanned in isolation, so only the `/Users/alice`
         // fragment on the first row matched and became clickable.