feat: raw fetch - a sanctioned intake for a URL into incoming/, HTML as received plus derived text (#120)

Files changed:
- CHANGES.md
- README.md
- VERSION
- instructions/wiki-ingest/SKILL.md
- raw/CONTRACT.md
- tools/CONTRACT.md
- tools/README.md
- tools/chemenu/cli_contract.py
- tools/chemenu/commands/raw_cmd.py
- tools/chemenu/tests/test_cli.py
- tools/chemenu/tests/test_portability.py
- tools/chemenu/tests/test_raw_fetch.py
- tools/chemenu/web_capture.py

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01SnAJ7Z3CpVD3PRbN73QtU2

README.md

@@ -207,6 +207,12 @@ A document can also arrive from outside, through the MCP server's optional `subm
 reviews and promotes it with `wikitool upload accept` before step 1 above applies - see
 [instructions/ingest-queue.md](instructions/ingest-queue.md).
 
+A web page needs no download of your own: tell the LLM `Ingest https://example.org/post`, and
+`tools/wikitool raw fetch` puts the page into `incoming/` - the HTML exactly as received, plus a
+text derived from it with a header recording where and when it was fetched. Behind a paywall or a
+login, save the page from your browser into `incoming/` (HTML only) instead; the LLM derives the
+same text from that file with `raw fetch --html`. See [raw/CONTRACT.md](raw/CONTRACT.md).
+
 ### Querying Knowledge
 
 Ask questions naturally: