Add settings page for tag-to-company mappings and auto-create Paperclip projects

When a case is created, a Paperclip project is now automatically created in
the correct company based on the appeal_subtype tag. Tag-to-company mappings
are managed via a new Settings page that pulls companies from Paperclip DB.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

web/app.py

@@ -2090,6 +2090,71 @@ async def api_paperclip_create_project(req: PaperclipProjectRequest):
     return project
 
 
+# ── Settings: Tag → Company Mappings ──────────────────────────────
+
+@app.get("/api/settings/paperclip-companies")
+async def api_paperclip_companies():
+    """List all companies from Paperclip's DB."""
+    pc_url = os.environ.get(
+        "PAPERCLIP_DB_URL", "postgresql://paperclip:paperclip@127.0.0.1:54329/paperclip"
+    )
+    try:
+        conn = await asyncpg.connect(pc_url)
+        try:
+            rows = await conn.fetch(
+                "SELECT id, name, identifier FROM companies ORDER BY name"
+            )
+            return [{"id": str(r["id"]), "name": r["name"], "identifier": r.get("identifier", "")} for r in rows]
+        finally:
+            await conn.close()
+    except Exception as e:
+        raise HTTPException(502, f"Cannot reach Paperclip DB: {e}")
+
+
+@app.get("/api/settings/tag-mappings")
+async def api_get_tag_mappings():
+    """Get all tag → company mappings."""
+    pool = await db.get_pool()
+    rows = await pool.fetch(
+        "SELECT id, tag, tag_label, company_id, company_name, created_at FROM tag_company_mappings ORDER BY tag"
+    )
+    return [dict(r) for r in rows]
+
+
+class TagMappingRequest(BaseModel):
+    tag: str
+    tag_label: str = ""
+    company_id: str
+    company_name: str = ""
+
+
+@app.post("/api/settings/tag-mappings")
+async def api_add_tag_mapping(req: TagMappingRequest):
+    """Add a tag → company mapping."""
+    pool = await db.get_pool()
+    try:
+        row = await pool.fetchrow(
+            """INSERT INTO tag_company_mappings (tag, tag_label, company_id, company_name)
+               VALUES ($1, $2, $3, $4)
+               ON CONFLICT (tag, company_id) DO UPDATE SET tag_label = $2, company_name = $4
+               RETURNING id, tag, tag_label, company_id, company_name""",
+            req.tag, req.tag_label, req.company_id, req.company_name,
+        )
+        return dict(row)
+    except Exception as e:
+        raise HTTPException(400, str(e))
+
+
+@app.delete("/api/settings/tag-mappings/{mapping_id}")
+async def api_delete_tag_mapping(mapping_id: str):
+    """Delete a tag → company mapping."""
+    pool = await db.get_pool()
+    result = await pool.execute("DELETE FROM tag_company_mappings WHERE id = $1::uuid", mapping_id)
+    if result == "DELETE 0":
+        raise HTTPException(404, "Mapping not found")
+    return {"ok": True}
+
+
 # ── Skill Management API ───────────────────────────────────────────