Add a Language Gate - no dimension currently checks language requirements (#275)

Nothing in the framework checks a posting's language requirements
against what the candidate actually speaks. It is not one of the five
Scoring Dimensions in 04-job-evaluation.md, it is not checked in
/scrape's Step 3 fit assessment, and it is not a field in /rank's JSON
output - even though /apply's Step 1 already extracts a posting's
required language generically, with nowhere to report a mismatch to.

This adds a Language Gate, structured like the existing Eligibility
Gate (read the posting, classify against profile data, hard-stop on a
real mismatch), built on a new structured Languages table in CLAUDE.md
/ 01-candidate-profile.md. /setup now asks for it directly (Path C), or
infers it from a CV/LinkedIn export (Paths A/B - LinkedIn exports
already carry a self-rated Languages section).

The gate compares a posting's stated language requirements against
that table with three outcomes:

- Requires a language not declared at all -> hard FAIL, never
  presented.
- Requires a higher level in a language that is declared (e.g. "fluent
  English" against a declared B1/B2) -> FLAG, not an auto-reject -
  scored and drafted normally, with the gap surfaced so the candidate
  judges it themselves (a "fluent" bar reads very differently from a
  strict employer vs. one that's flexible on it).
- Requires a language at or below the declared level -> clean PASS.

Wired through the three places that need it: /scrape (Step 3), /rank
(new language_gate/language_note fields alongside the existing
location veto - both are now persisted to seen_jobs.json, not just
used transiently to decide one run's shortlist), and /apply (Step 1's
language extraction now has somewhere to report to).

Out of scope, deliberately: this does not touch the free-form
Deal-breakers list or how it's used elsewhere (e.g. Scoring Dimension
4's relocation check) - that's a separate question this change takes
no position on.

Validated with two live-testing passes against real, unfetched
postings (not fabricated text) across 3 portals and 3 market languages
(Danish, German, Spanish/Argentina): 8/8 postings gated correctly in
the first pass, including ambiguous real-world wording ("you
communicate well in English") a rigid rule would have gotten wrong. A
second pass, run specifically to force a hard-FAIL case, found one
(a Danish posting requiring the ability to read Danish) and confirmed
it persists correctly and would be excluded from /rank's shortlist.

Co-authored-by: Claude Sonnet 5 <noreply@anthropic.com>

README.md

@@ -308,7 +308,7 @@ Everything above adds up to an extension model, so here it is stated plainly. Th
 
 1. **Portal skills** - the module system for job boards. Every `*-search` skill is a self-contained folder under `.agents/skills/` with the same contract (a `search`/`detail` CLI, `--format json|table|plain` output, an `enabled:` flag in its `SKILL.md`, its own tests). `/scrape` auto-discovers any installed skill that follows the contract - nothing to register, nothing to wire up. `/add-portal` generates new ones; the [community portal index](https://github.com/MadsLorentzen/ai-job-search/discussions/78) catalogs the ones other forks have built.
 2. **Document templates** - `/add-template` registers any CV or cover-letter toolchain that compiles to PDF from the command line, LaTeX or otherwise.
-3. **Evaluation criteria** - deal-breakers and preferences in your profile are free-form, and the evaluation rubric scores against whatever you put there. "Strong parental-leave terms", "minimum salary X per my union's scale", "no on-call" - each is one profile line, no code, and it carries real weight in `/rank` and `/apply` fit evaluations.
+3. **Evaluation criteria** - deal-breakers and preferences in your profile are free-form, and the evaluation rubric scores against whatever you put there. "Strong parental-leave terms", "minimum salary X per my union's scale", "no on-call" - each is one profile line, no code, and it carries real weight in `/rank` and `/apply` fit evaluations. Language is the one deal-breaker type with dedicated, structured handling: `/setup` captures every language you work in and your level (asked directly, or inferred from your CV/LinkedIn export) into a `Languages` table, and the Language Gate (`04-job-evaluation.md`) hard-rejects a posting that requires a language you haven't declared at all, while flagging - not auto-rejecting - one that asks for a higher level than you declared in a language you do work in, so a borderline case (a strict "fluent" bar against your own B1/B2, say) gets your judgment instead of a silent drop.
 
 **Borrowing a portal skill from another fork** is the intended way to get a board that upstream doesn't ship: find it in the [portal index](https://github.com/MadsLorentzen/ai-job-search/discussions/78), open that fork, and copy the one folder into your own `.agents/skills/`. Before you run it: