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/app/src/composer/draft/create-flow.ts

@@ -1,7 +1,10 @@
 import { useCallback, useMemo, useReducer } from "react";
 import { useTranslation } from "react-i18next";
 import type { ComposerAttachment } from "@/attachments/types";
-import { splitComposerAttachmentsForSubmit } from "@/composer/attachments/submit";
+import {
+  resolveComposerAttachmentSubmitFormat,
+  splitComposerAttachmentsForSubmit,
+} from "@/composer/attachments/submit";
 import { useCreateFlowStore } from "@/stores/create-flow-store";
 import { useSessionStore } from "@/stores/session-store";
 import {
@@ -236,10 +239,23 @@ export function useDraftAgentCreateFlow<TDraftAgent, TCreateResult>({
       }
 
       dispatch({ type: "DRAFT_SET_ERROR", message: "" });
-      const wirePayload = splitComposerAttachmentsForSubmit(attachments);
+      const trimmedPrompt = text.trim();
+      const pendingServerId = getPendingServerId();
+      if (!pendingServerId) {
+        const error = new Error(t("composer.errors.noHostSelected"));
+        dispatch({ type: "DRAFT_SET_ERROR", message: error.message });
+        throw error;
+      }
+      const supportsForgeSearch =
+        useSessionStore.getState().sessions[pendingServerId]?.serverInfo?.features?.forgeSearch ===
+        true;
+      const wirePayload = splitComposerAttachmentsForSubmit(attachments, {
+        format: resolveComposerAttachmentSubmitFormat({
+          supportsForgeAttachments: supportsForgeSearch,
+        }),
+      });
       const images = wirePayload.images;
 
-      const trimmedPrompt = text.trim();
       const hasAttachmentContent = images.length > 0 || wirePayload.attachments.length > 0;
       if (!trimmedPrompt && !hasAttachmentContent && !allowEmptyText) {
         const error = new Error(t("composer.errors.initialPromptRequired"));
@@ -258,13 +274,6 @@ export function useDraftAgentCreateFlow<TDraftAgent, TCreateResult>({
         throw error;
       }
 
-      const pendingServerId = getPendingServerId();
-      if (!pendingServerId) {
-        const error = new Error(t("composer.errors.noHostSelected"));
-        dispatch({ type: "DRAFT_SET_ERROR", message: error.message });
-        throw error;
-      }
-
       const attempt: CreateAttempt = {
         clientMessageId: generateMessageId(),
         text: trimmedPrompt,