[bug] quick-router: leading please on web_search lookups falls through to the LLM

[kurosawareiji7007-hub]

Summary

web_search_request already strips a trailing please from the extracted query (covered by web_search_query_drops_trailing_please). A leading please was never stripped, so the start-anchored look-up / search prefixes miss equally natural polite forms and fall through to the LLM.

Repro (on main)

utterance	on main	expected
Please look up the best mesh router	ABSTAIN	web_search{query: the best mesh router}
Please search the web for matter support	ABSTAIN	web_search{query: matter support}
Please look up the best mesh router please	ABSTAIN	web_search{query: the best mesh router}
Please search online for ESP32 C6	ABSTAIN	web_search{query: esp32 c6}

Look up the best mesh router please / Search the web for matter support already route today.

Root cause

The look-up / search prefix loop in web_search_request is start-anchored. Leading please keeps the string from matching any prefix, even though trailing politeness is already cleaned from the query.

Proposed fix

Strip a leading please at the top of web_search_request (before memory/remind abstains and the prefix loop), mirroring news (#908), time (#906), scene/routine (#894), and shopping-list (#843). Negatives stay off search (please help me); reminder forms stay off immediate web_search (please remind me to check the tesla stock price in 20 minutes).

Acceptance

• Leading-please look-up / search forms route to web_search
• Existing trailing-please query cleaning unchanged
• Focused regression test fails on main, passes with the fix
• No prompt growth; 4096 Jetson contract untouched

Labels / scope

Tool-dispatch correctness (deterministic quick-router). Same contribution bucket as #843 / #894 / #906 / #908.

[kurosawareiji7007-hub]

Working on this. Local fix + regression test ready on fix/quick-router-web-search-leading-please. Will open the PR as soon as one of my current open PRs (#907 / #909) merges (repo enforces max 2 open PRs per author).