sites: the instance writes its own site handlers as JSON files under sites/, the stack's learn.microsoft.com handlers become data files in the same format (#210); 10.0.0-beta.4

Files changed:
- .gitignore
- AGENTS.md
- CHANGES.md
- VERSION
- docs/explanation/architecture.md
- docs/how-to/README.md
- docs/how-to/write-a-site-handler.md
- docs/reference/commands/instance-health.md
- docs/reference/commands/raw-material-and-uploads.md
- docs/reference/configuration.md
- instructions/dev/doc-pull-through.md
- raw/CONTRACT.md
- sites/CONTRACT.md
- tools/CONTRACT.md
- tools/README.md
- tools/chemenu/commands/dist_cmd.py
- tools/chemenu/commands/docs_verify.py
- tools/chemenu/commands/doctor.py
- tools/chemenu/commands/git_publish.py
- tools/chemenu/commands/raw/fetch.py
- tools/chemenu/ownership.py
- tools/chemenu/sites/__init__.py
- tools/chemenu/sites/data.py
- tools/chemenu/sites/handlers/learn-microsoft-powershell-module.json
- tools/chemenu/sites/handlers/learn-microsoft.json
- tools/chemenu/sites/learn_microsoft.py
- tools/chemenu/sites/site.schema.json
- tools/chemenu/tests/test_dist_cmd.py
- tools/chemenu/tests/test_doctor.py
- tools/chemenu/tests/test_site_files.py
- tools/chemenu/toc.py

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

docs/reference/commands/instance-health.md

@@ -43,6 +43,7 @@ tools/wikitool doctor --json
 - Settings (`settings-instance`, `settings-checkout`, `settings-secrets`): one line per tier. `wikitool.json` and `.wikitool-local.json` each present or absent - absent is `OK` - and a `FAIL` naming file, key and the right tier when a value sits in the wrong file, a secret or a committed private field holds a plain value, or a value fails its field; a section this version does not read is a `WARN`. For the references: how many resolve, never a value - an unresolvable one is a `FAIL`, one 1Password will not hand out until a human unlocks it a `WARN`.
 - Session id source: `OK` for `WIKITOOL_SESSION_ID` or a registered harness variable, `WARN` only for the bare parent-pid fallback.
 - Telemetry: on or off and why - installation-form default, the `telemetry` section of `.wikitool-local.json`, or `WIKI_TRACE` - and the current session's count and byte total against both caps; never a `FAIL`. A `WARN` when that section is not read as written - unreadable JSON, not an object, `enabled` not a JSON boolean, a cap not a positive integer, or an unknown key - naming the field; telemetry itself drops or reinterprets such a value without a word, so this is where it shows.
+- Site handlers (`site-handlers`): every file in `sites/` is read against the handler schema and the rules the schema cannot state; `FAIL` for a file that cannot be used, naming the file and the reason, and `OK` listing the instance's handlers, each one that replaces a stack handler (the same host and path) named as such.
 - Exits 1 only on a `FAIL`; a missing remote, session id or `VERSION` is a `WARN`, not a fault.
 - Read-only and exempt from the Iteration Budget Gate.
 

docs/reference/commands/raw-material-and-uploads.md

@@ -55,7 +55,7 @@ tools/wikitool raw fetch --html incoming/post.html --url https://example.org/blo
 - The `.html` holds the response body byte for byte. The `.md` starts with a fixed header block (`fetched_by`, `url`, `final_url`, `retrieved`, `http_status`, `content_type`, `charset`, `title`, `derived_from`) followed by the derived text. A page of a website with a site handler adds `site`, and `requested_url` when the URL fetched is not the one typed.
 - Character set, in this order: byte-order mark, the HTTP `Content-Type` charset, a `<meta>` declaration in the first 4 KiB, UTF-8. Undecodable bytes are replaced with U+FFFD and reported; the header names the charset and where it came from.
 - Derived text: the content root is `<main>`, else the single `<article>`, else `<body>`; `script`, `style`, `noscript`, `nav`, `header`, `footer`, `aside`, `form`, `template` and `svg` are dropped below it. Headings, lists, code, tables and links (made absolute) become Markdown. The same bytes always give the same text.
-- Site handlers: for the pages of a website the stack knows (today `learn.microsoft.com`), `raw fetch <url>` fetches the standard form of the URL (the locale segment becomes `en-us`, the `view=` query stays) and `<url>` as typed goes into the header as `requested_url`; `url` is the form fetched. The handler also removes the page furniture the website renders around the article from the derived text - never from the `.html` - and prints hints that apply to this page as `CHECK` lines: act on one before accepting. `--html --url <url>` removes the same furniture but keeps the URL as typed. A URL no handler claims is handled as before. The `sites` section of the settings switches handlers off, sets the locale and adds hint lines of the instance's own per host.
+- Site handlers: for the pages of a website the stack or the instance knows (the stack's today: `learn.microsoft.com`; the instance's are JSON files in `sites/`), `raw fetch <url>` fetches the standard form of the URL (the locale segment becomes `en-us`, the `view=` query stays) and `<url>` as typed goes into the header as `requested_url`; `url` is the form fetched. The handler also removes the page furniture the website renders around the article from the derived text - never from the `.html` - and prints hints that apply to this page as `CHECK` lines: act on one before accepting. `--html --url <url>` removes the same furniture but keeps the URL as typed. A URL no handler claims is handled as before. The header names an instance's handler as `<name> (instance)`. A handler file of the instance that cannot be used, and names the URL's host or no readable host, stops the fetch before anything is fetched or written. The `sites` section of the settings switches handlers off, sets the locale and adds hint lines of the instance's own per host.
 - The stem is the URL's last path segment without its extension, else its host name - ASCII, lowercase, `-`-separated, at most 60 characters; `--name` overrides it.
 - A `text/plain` or `text/markdown` response is stored as received as `.txt`/`.md`; any other non-HTML response (PDF, image, ...) as received under the extension of its content type. Neither gets a derived file or a header.
 - Only `http`/`https`, on every redirect hop too. 30 s for the whole transfer, 25 MiB at most. No cookies, no JavaScript: a derived text under 200 characters is written, with a warning to read it before accepting.
@@ -74,7 +74,7 @@ tools/wikitool raw fetch --html incoming/post.html --url https://example.org/blo
 
 - `0` - success
 - `1` - The URL is not `http`/`https` (also after a redirect), or neither or both of `<url>` and `--html` were given
-- `1` - The `sites` section of the settings is malformed, or `disabled` names a handler that does not exist
+- `1` - The `sites` section of the settings is malformed, `disabled` names a handler that does not exist, or a file in `sites/` cannot be used and names this URL's host (or none can be read)
 - `1` - A target file already exists in `incoming/`
 - `1` - The server answered with an HTTP error, could not be reached, took longer than 30 s, or sent more than 25 MiB
 - `1` - raw fetch --html: `--url` is missing, the file is not directly in `incoming/` or does not exist, or `incoming/<stem>.md` already exists
@@ -82,6 +82,7 @@ tools/wikitool raw fetch --html incoming/post.html --url https://example.org/blo
 **See also**
 
 - `raw/CONTRACT.md` "Getting a URL in: `raw fetch`" - the rules and why
+- `sites/CONTRACT.md` - the instance's own handler files
 - `docs/reference/configuration.md` - the `sites` section, which tunes the site handlers
 - `wikitool raw accept` - promotes the written files into `raw/`
 - `instructions/wiki-ingest/SKILL.md` - where a URL to ingest starts