feat: FEAT-293 Standalone-practice discoverability + propatheia content fix

[MP2EZ]

Closes FEAT-293

Standalone practices (breathing, body scan, reflection, and especially the Stoic control-sorting drill) were reachable only from deep inside Learn. This surfaces them from Home.

Scope narrowed from the original AC1. "A Home entry and/or a loop variation slot" was a material fork, not a hedge: no variation slot exists (zero grep hits for variation; StepConfig has no affordance to host one, and adding it mutates a crisis- and philosopher-reviewed config), and daily_loop:false in .config/.env.production means a loop-slot-only implementation would have been invisible to every real user the day it merged — making AC1's own words ("reachable from a primary surface") false in production. Loop slot deferred; Home entry ships.

What ships

• Home: fixed-height "Practices / Explore" row below checkInSection, not a fifth CheckInCard. checkInSection is flex:1 and each card inside is also flex:1 with no ScrollView, so a fifth card squeezes all of them. The row also survives FEAT-298 retiring the three time-of-day cards.
• New PracticeLibrary root screen. Sorting drill featured and named by principle, carrying the Enchiridion 1 framing and a "Read the full principle: Sphere Sovereignty" link to Module 3 — no context-free launch, since the drill's answer key encodes a counterintuitive doctrine that reads as arbitrary once Module 3's prose is out of view. Practices group under their own principle: breathing/body scan under Aware Presence (never labelled Stoic), reserve clause with Sphere Sovereignty (it is hypexhairesis).
• Launch switch extracted from PracticeTab into a pure resolvePracticeRoute, shared by Learn and the library rather than two switches that can drift.
• SortingPractice.scenarios is now optional, resolved by a wrapper that self-loads module content. This also repairs the pre-existing /sorting deep link, which could never have supplied a scenarios array.
• No score/tally/streak/badge. Signed feedback copy and VIRTUE_CHECK_FEEDBACK untouched. The citation is imported from PRACTICE_QUOTES, not retyped.

Content safety fix — 5 cards, live in Learn today

medical-test-anxiety marked "Your anxiety about an upcoming medical test result" as in-control, explaining the anxiety itself is up to you. That conflates propatheia — the involuntary first movement, which classical Stoicism holds is not up to us — with assent. On a primary surface without Module 3's prose it tells a user with elevated GAD-7 that their anxiety is their own doing, and flags "Not Quite" when they disagree.

Rewritten to sort the response, first wave of fear moved to notInControl. The philosopher's review of that rewrite found it had made the rest of the deck inconsistent with its own new standard:

Card	Fix
medical-test-anxiety	text/explanation rewritten; two avoidance-shaped inControl items replaced
political-response	its explanation contradicted its own notInControl list — both render in one viewport
traffic-cutoff	asserted the arising anger is chosen
event-interpretation	highest risk — stated the conflation as doctrine, on the card most likely to be loaded with a real difficult event
vacation-weather	listed an outcome ("finding enjoyment") as a controllable

friend-no-reply was already correct and served as the model; six other cards verified clean.

Tests

AC3 ("no regression to existing Learn-launched entry points") had no mechanical pin — zero tests referenced PracticeTab. Added:

• 13 cases locking resolvePracticeRoute param-for-param to the original inline switch, including its default durations; plus pins that the drill's citation resolves to Epictetus rather than silently falling back to the breathing quote, and that every catalog entry is filed under its own principle (a mislabel would propagate into the Insights engagement chart).
• 6 render cases for SortingPracticeRoute, which is now the rendered component for the pre-existing SortingPractice route. The Maestro suite deliberately does not walk practice flows, so this path had no on-device gate. Load-bearing case: the Learn path passes scenarios through with no module load and no spinner frame.
• 1 case in RootCrisisButton.test.tsx pinning that PracticeLibrary keeps the overlay in standard mode — unknown routes fall through to standard, but safe-by-accident is not a contract.

Verification

npm run precommit          exit 0 — safety 108, clinical 106, unit 587, privacy 51
npm run test:accessibility 11 suites, 87 passed
lint baseline              557 -> 555 (improved)

npm run e2e:safety (FULL suite — core/navigation is cross-cutting)
  PASS  crisis-button-reachability
  PASS  daily-loop-quick-depth
  PASS  gad7-severe
  PASS  phq9-severe-completion
  PASS  q9-single-alert

Follow-up (not in this PR)

Philosopher sequencing note: medical-test-anxiety is card 3 of 12. On a wrong answer the announcement lands hard for a user with a real pending result. Recommend re-ordering it later in the deck, or excluding it from the first-served set on a Home cold-start.

🤖 Generated with Claude Code