feat(claude): nudge fresh sessions to load the pql + clide skills (T-490)

A fresh Claude session now gets a one-line preamble (clideSkillsNote) telling it
to reach for the bundled pql + clide skills from its first turn rather than
rediscovering the workflows. Layered onto clideContextNote in the single
--append-system-prompt.

Gated on a NEW session (!spec.resume && !spec.isFork): new tabs and the
post-/clear respawn spawn with resume:false and get it; the account-change
respawn (T-480) and real resumes carry prior context (resume:true), and forks
inherit their source — none are re-nagged. Both skills already ship (pql
user-scope, clide repo-scope), so no precursor was needed.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

CHANGELOG.md

@@ -54,6 +54,9 @@ heading, and (b) bumping `pubspec.yaml` `version:` in the same commit.
 
 ### Changed
 
+- **Fresh Claude sessions are nudged to use the bundled skills.** New tabs and
+  post-`/clear` respawns get a one-line prompt to load the `pql` + `clide`
+  skills from the first turn; resumed/forked sessions are left alone. (T-490)
 - **Claude meta sidebar facelift.** The Activity, Team, and Config tabs render
   their sections as elevated cards with small-caps headers, matching the
   settings overlay's card design. (T-158)