Expand DeckDoc into a full-system diagnostic platform

[deucebucket]

Summary

Reframes DeckDoc as a full-system Steam Deck diagnostic and incident-response platform rather than a black-screen utility.

• fixes remaining issue New Module: Core Dump / Crash Report Analysis (coredumpctl) #2–New Module: DXVK/VKD3D GPU Hang State Differentiation #9 evidence boundaries and false positives;
• expands the README, roadmap, research catalog, and diagnostic-center wiki;
• adds an opt-in bounded continuous incident probe;
• adds dock/USB-C/PD/Alt Mode/Ethernet/display diagnostics;
• adds the read-only DeckDoc Rescue collector and unsigned alpha image builder;
• adds a one-time approved, root-owned exact-command diagnostic broker;
• adds DeckMD, a private local-only GitHub Pages symptom checker with 128 facts, adaptive related checks, and 15 ranked branches;
• adds CI, link/schema validation, and 27 regression/safety tests.

Safety boundaries

• Normal diagnostics and Rescue do not remediate or write the installed disk.
• The probe is explicit opt-in and never starts from normal setup.
• Dock voltage/current/power is exported telemetry, not electrical certification.
• Passwordless authorization excludes arbitrary arguments, paths, environments, shells, and remediation.
• Rescue remains an unsigned alpha, not a Valve recovery image.
• DeckMD rankings are diagnostic priorities, not probabilities or hardware verdicts.

Validation

• bash -n deckdoc.sh setup.sh modules/*.sh probe/*.sh bootprobe/*.sh privileged/* tests/*.sh
• bash tests/test_runner.sh — all 27 tests pass locally.
• node tests/validate_deckmd.js — 8 sections, 128 unique facts, 15 branches.
• node tests/validate_links.js — 31 Markdown files plus site assets.
• git diff --check
• Correct live Galileo/OLED Deck: all 27 SteamOS-compatible tests pass; fresh read-only report launched all 17 modules.
• Isolated GUI screenshot service was unavailable; responsive CSS, reduced-motion, asset loading, JS syntax, schema, and progressive-display behavior were validated. Visual browser review remains before marking ready.

Follow-up trackers

#15, #16, #17, #18, #19, #20, #21, #22, and #23 scope production hardening and the next diagnostic gaps.

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