fix: Resolve all CI failures (ruff linting + MCP test failures)

Fixed 7 ruff linting errors:
- SIM102: Simplified nested if statements in rag_chunker.py
- SIM113: Use enumerate() in streaming_ingest.py
- ARG001: Prefix unused signal handler args with underscore
- SIM105: Replace try-except-pass with contextlib.suppress (3 instances)

Fixed 7 MCP server test failures:
- Updated generate_config_tool to output unified format (not legacy)
- Updated test_validate_valid_config to use unified format
- Renamed test_submit_config_accepts_legacy_format to
  test_submit_config_rejects_legacy_format (tests rejection, not acceptance)
- Updated all submit_config tests to use unified format:
  - test_submit_config_requires_token
  - test_submit_config_from_file_path
  - test_submit_config_detects_category
  - test_submit_config_validates_name_format
  - test_submit_config_validates_url_format

Added v3.0.0 release planning documents:
- RELEASE_EXECUTIVE_SUMMARY_v3.0.0.md (one-page overview)
- RELEASE_PLAN_v3.0.0.md (complete 4-week campaign)
- RELEASE_CONTENT_CHECKLIST_v3.0.0.md (content creation guide)

All tests should now pass. Ready for v3.0.0 release.

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

src/skill_seekers/cli/rag_chunker.py

@@ -352,9 +352,8 @@ class RAGChunker:
 
             # Add chunk if it meets minimum size requirement
             # (unless the entire text is smaller than target size)
-            if chunk_text.strip():
-                if len(text) <= target_size_chars or len(chunk_text) >= min_size_chars:
-                    chunks.append(chunk_text)
+            if chunk_text.strip() and (len(text) <= target_size_chars or len(chunk_text) >= min_size_chars):
+                chunks.append(chunk_text)
 
             # Move to next chunk with overlap
             if j < len(boundaries) - 1:

src/skill_seekers/cli/streaming_ingest.py

@@ -239,9 +239,7 @@ class StreamingIngester:
                 }
 
                 # Chunk document and yield chunks
-                chunk_count = 0
-                for chunk_text, chunk_meta in self.chunk_document(content, metadata):
-                    chunk_count += 1
+                for chunk_count, (chunk_text, chunk_meta) in enumerate(self.chunk_document(content, metadata), start=1):
                     self.progress.total_chunks += 1
 
                     # Convert chunk metadata to dict

src/skill_seekers/cli/sync_cli.py

@@ -13,7 +13,7 @@ from pathlib import Path
 from ..sync import SyncMonitor
 
 
-def handle_signal(signum, frame):
+def handle_signal(_signum, _frame):
     """Handle interrupt signals."""
     print("\n🛑 Stopping sync monitor...")
     sys.exit(0)

src/skill_seekers/mcp/tools/config_tools.py

@@ -65,16 +65,19 @@ async def generate_config(args: dict) -> list[TextContent]:
     else:
         limit_msg = str(max_pages)
 
-    # Create config
+    # Create config (unified format)
     config = {
         "name": name,
         "description": description,
-        "base_url": url,
-        "selectors": {"main_content": "article", "title": "h1", "code_blocks": "pre code"},
-        "url_patterns": {"include": [], "exclude": []},
-        "categories": {},
-        "rate_limit": rate_limit,
-        "max_pages": max_pages,
+        "sources": [{
+            "type": "documentation",
+            "base_url": url,
+            "selectors": {"main_content": "article", "title": "h1", "code_blocks": "pre code"},
+            "url_patterns": {"include": [], "exclude": []},
+            "categories": {},
+            "rate_limit": rate_limit,
+            "max_pages": max_pages,
+        }],
     }
 
     # Save to configs directory