Extend pattern 11 to cover repeated sentence openings (v2.9.2)

[somtri]

Fixes #206.

The issue reports narrative prose where consecutive sentences all open on the same word, usually "she" or "he". The reporter counted 147 sentence-initial "she" in one audiobook transcript, 34 doubled and 11 tripled.

I extended §11 instead of adding a numbered pattern. §11 already describes repetition-penalty machinery over-firing and cycling through synonyms for a single referent, and a repeated sentence opening is that machinery failing to fire instead. Same defect, opposite direction, so the count stays at 33. #171 was closed with the note that a new numbered pattern carries permanent prompt and maintenance cost and that a narrow idea might still fit as an extension to an existing rule. This looked like that case.

What changed:

• §11 picks up the inverse tell, the reporter's example, and the three fixes from the issue: merge the sentences, hand the subject role to something else, or open on the action.
• A new false-positive bullet for deliberate anaphora. It stands alone rather than folding into the staccato-drama bullet, because "She came. She saw. She conquered." is a different false positive from clipped fragments and that section runs one tell per bullet.
• README row 11, a Version History line, and a 2.9.2 bump across SKILL.md, README, and plugin.json, per the AGENTS.md sync contract.

I left out the fourth remedy in the issue, the threshold flagging a starting token used more than twice in a row. It needs somewhere to execute, and what ships here is a prompt.

The "After" example still opens on "She," which looks like an oversight and is not. The tell is the run of three, not the word. An example that dodged the pronoun would teach pronoun-avoidance instead of consolidation.

python scripts/validate-package.py passes at v2.9.2. SKILL.md is 419 lines against the 500-line budget.