fork: add Gitea/Forgejo source support for company skills

Reintroduce Gitea/Forgejo as a skill import source on dev only, since
the fork deploys against git.farh.net. Pasting a Gitea/Forgejo repo
URL into the skills sidebar mirrors the existing GitHub experience:
pin to a commit SHA, check for updates, read repo files.

Server: new gitea-fetch.ts (URL builders, probe-cache helpers) and
gitea-skills.ts (parse, probe, pin, tree, text, branch). Dispatch in
readUrlSkillImports probes /api/v1/version and routes non-github.com
hosts into the new readGiteaUrlSkillImports branch. updateStatus and
readFile get a gitea arm alongside the github/skills_sh arm. Audit
falls through to "remote not supported" the same way github does.

UI: Server icon, Gitea source label, gitea in the "external" source
class, Pin/Update UI gate widened to sourceType === "gitea". CLI help
text updated. Existing github code is left byte-for-byte unchanged
(wrapped in isGitHubDotCom) so dev <-> master syncs stay clean.

PAT support, gitea portability descriptors, and gitea audit are
deliberate follow-ups. Detection requires /api/v1/version to return
Gitea-shaped JSON; the per-host result is cached for process lifetime
with FIFO eviction at 1024 entries. Non-Gitea hosts fall through to
the existing raw-markdown url branch.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

server/src/__tests__/company-skills-routes.test.ts

@@ -444,6 +444,53 @@ describe("company skill mutation permissions", () => {
     });
   });
 
+  it("imports Gitea skills and tracks the import with skillRef null (non-github.com)", async () => {
+    mockCompanySkillService.importFromSource.mockResolvedValue({
+      imported: [
+        {
+          id: "skill-1",
+          companyId: "company-1",
+          key: "git.example.com/acme/remote-skill/web",
+          slug: "web",
+          name: "Remote Skill",
+          description: null,
+          markdown: "# Remote",
+          sourceType: "gitea",
+          sourceLocator: "https://git.example.com/acme/remote-skill",
+          sourceRef: "abc123abc123abc123abc123abc123abc123abcd",
+          trustLevel: "markdown_only",
+          compatibility: "compatible",
+          fileInventory: [],
+          metadata: {
+            hostname: "git.example.com",
+            owner: "acme",
+            repo: "remote-skill",
+            sourceKind: "gitea",
+          },
+          createdAt: new Date(),
+          updatedAt: new Date(),
+        },
+      ],
+      warnings: [],
+    });
+
+    const res = await request(await createApp({
+      type: "board",
+      userId: "local-board",
+      companyIds: ["company-1"],
+      source: "local_implicit",
+      isInstanceAdmin: false,
+    }))
+      .post("/api/companies/company-1/skills/import")
+      .send({ source: "https://git.example.com/acme/remote-skill" });
+
+    expect([200, 201], JSON.stringify(res.body)).toContain(res.status);
+    expect(mockTrackSkillImported).toHaveBeenCalledWith(expect.anything(), {
+      sourceType: "gitea",
+      skillRef: null,
+    });
+  });
+
   it("blocks same-company agents without management permission from mutating company skills", async () => {
     mockAgentService.getById.mockResolvedValue({
       id: "agent-1",