feat(mavweb): /ecosystem page consuming Nexus/Praxis/Hexis + shell fixes

Add a read-only /ecosystem page that consumes the sibling services'
JSON APIs (Nexus entities, Praxis attention, Hexis capabilities),
fetched concurrently with honest per-panel error states. Siblings stay
headless — mavweb is their human surface (arch §16). Wired via mavweb
-nexus/-praxis/-hexis flags; mavweb joins the ecosystem compose network.

Fix mobile horizontal overflow across all pages: .content is a flex
child with default min-width:auto, so it refused to shrink below the
tables' intrinsic width. min-width:0 lets wide tables pan inside .scroll
instead of dragging the page sideways. Verified via CDP geometry check
(scrollWidth === clientWidth at 430px).

Also includes in-progress Ethos UI redesign, ecosystem deploy compose,
and planning docs.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

PROGRESS.md

@@ -1,4 +1,10 @@
-## Maven — current state (2026-07-06)
+## Maven — current state (updated 2026-07-18)
+
+Architecture decision: the target resident router/phraser is the locally
+trained Qwen3-1.7B model. Older LFM references below describe the currently
+deployed/historical stack, not the target checkpoint. RU CPT has a successful
+full-weight checkpoint at step 1000/8077; evaluation and Qwen3 SFT tooling are
+tracked in `docs/plans/2026-07-18-qwen3-resident-training-eval.md`.
 
 Consolidated status. The reactive↔proactive core is closed and testable through
 the web PWA. The SPEC's open items 1–7 are landed (protocol doc, away-channel