feat(forge): pluggable forge abstraction + GitLab and Gitea/Forgejo/Codeberg (#1913)

* refactor(forge): forge-neutral foundation (GitHub-only)

Decouple git-hosting from GitHub behind a neutral abstraction (issue #1616), GitHub-only for now; existing GitHub behaviour is unchanged.

- Forge manifest, neutral ForgeService contract, forge registry + resolver, and a client forge-module registry.
- GitHub code renamed to the neutral shape; PR/Issue attachment wording preserved.
- forge.search.response enums parse tolerantly (unknown kind/auth state degrade instead of breaking the client).
- createPullRequest reports typed CLI/auth errors instead of a generic message.
- forge-resolver host/remote caches are LRU-bounded.
- Forge host trust is explicit: only a known cloud host or a CLI-authenticated host is ever talked to; an unauthenticated GitHub Enterprise host fails resolution instead of routing to github.com.
- Docs: forge-providers guide, glossary and i18n forge-copy conventions, architecture and rpc-namespacing terminology.
- Vitest React Native mocks (unistyles, svg, linking, lucide) consolidated into shared aliased test-stubs.

* feat(forge): GitLab adapter, forge-aware UI, pipelines and approvals

GitLab adapter over the glab CLI on the neutral contracts: MR status, forge-aware UI, pipeline tree, and N-of-M approvals.

- threadIsResolved is part of the neutral timeline item.
- Pipeline load failures show an error instead of an empty section.
- Manual pipeline jobs render as pending.
- Fork/detached MR head pipelines are fetched by MR iid (glab ci get --merge-request).

* feat(forge): Gitea family adapter (Gitea, Forgejo, Codeberg)

One adapter over the tea CLI serving Gitea, Forgejo, and Codeberg on the neutral contracts.

- CI status aggregates commit statuses and Actions runs together.
- Gitea's terminal "warning" state maps to failure on server and client.
- Gitea Actions check details are reachable from the PR pane by workflowRunId.

* refactor(forge): localize compatibility handling

* test(forge): expect normalized GitLab facts

---------

Co-authored-by: Mohamed Boudra <boudra.moha@gmail.com>

packages/protocol/tests/validation/ws-outbound.test.ts

@@ -142,4 +142,58 @@ const SourceSchema = z.object({
     const generated = await readFile(generatedWSOutboundPath, "utf8");
     expect(generated).toContain('from "../../validation/ws-outbound-schema-metadata.js"');
   });
+
+  it("accepts a forge.search.response envelope", () => {
+    const result = GeneratedWSOutboundMessageSchema.safeParse({
+      type: "session",
+      message: {
+        type: "forge.search.response",
+        payload: {
+          items: [
+            {
+              kind: "change_request",
+              number: 17,
+              title: "Fix search",
+              url: "https://gitlab.com/acme/repo/-/merge_requests/17",
+              state: "open",
+              body: null,
+              labels: [],
+            },
+          ],
+          authState: "authenticated",
+          error: null,
+          requestId: "search-forge",
+        },
+      },
+    });
+    expect(result.success).toBe(true);
+  });
+
+  it("accepts a legacy github_search_response envelope", () => {
+    const result = GeneratedWSOutboundMessageSchema.safeParse({
+      type: "session",
+      message: {
+        type: "github_search_response",
+        payload: {
+          items: [
+            {
+              kind: "pr",
+              number: 42,
+              title: "Legacy PR",
+              url: "https://github.com/acme/repo/pull/42",
+              state: "open",
+              body: null,
+              labels: [],
+            },
+          ],
+          featuresEnabled: true,
+          githubFeaturesEnabled: true,
+          authState: "authenticated",
+          error: null,
+          requestId: "search-github",
+        },
+      },
+    });
+    expect(result.success).toBe(true);
+  });
 });