v1 release prep: docs, zero-state, error handling, defaults

[proofofprints]

Summary

Addresses the blockers and top high-priority items from the v1 readiness audit. Every change is localized polish — no architectural or functional changes to core data flow. 8 targeted fixes across 7 files, +127/-29.

This is the last PR I'm planning before cutting a v1 tag and handing builds to external testers.

What this fixes

Blockers (docs + stale copy)

• README Quick Start — the old instructions pointed testers at a "Monitoring" tab that was deleted in the mobile miners refactor. Rewritten to use the current ASIC Miners → Add Device flow, plus a new Mobile Miners subsection covering the pairing code flow.
• README config paths — the old README said `%APPDATA%/com.proofofprints.popmanager/` for all Windows data, but in reality most operational state (miners, alerts, mobile miners, pool profiles, SMTP, etc.) lives in `%LOCALAPPDATA%\PoPManager\. Only preferences/history/uptime go to \%APPDATA%\`. Testers trying to back up their setup would have missed half their data. Now documents both directories with a per-file inventory.
• Settings → About "Supported Hardware" line — hardcoded "Iceriver KS0 / KS0 Pro / KS0 Ultra" despite the app supporting the full Iceriver KS0-KS5, Whatsminer M50/M56/M60/M66, and Antminer S19/S21 range. Testers with Antminers or Whatsminers would have seen that line and assumed their hardware was unsupported.
• New "First Launch on Windows" README section — covers the two things every first-time tester will ask about:
  • Windows SmartScreen "unrecognized app" warning (expected until code signing lands)
  • Windows Defender Firewall prompt for the optional mobile telemetry listener

High-priority first-impression fixes

• Dashboard zero-state welcome card — on a fresh install with no miners, the dashboard used to render 7 zero-value stat cards above a tiny empty-state hint. Now short-circuits to a full-viewport welcome card with "Add ASIC Miner" / "Add Mobile Miner" CTAs when both counts are zero. The existing inner "No miners found" hint is preserved for the asymmetric case (ASIC empty, mobile present or vice versa).

• Replace `window.alert()` with inline error banners — four call sites in the removal flows (`MinerList.tsx:986`, `MobileMinerDetail.tsx:126`, `MobileMinerList.tsx:711, 754`) used native browser `alert()` dialogs which look unprofessional on Windows. Now each confirmation modal has a red-tinted error banner that appears if the Tauri command rejects. MobileMinerList gets two separate error states (single-device and bulk) so each modal shows its own scoped error.

• Downgrade poll-cycle logs to debug — `info("Poll cycle start")` and `info("Poll cycle complete")` in Dashboard.tsx were firing every 45 seconds at info level. Testers opening `popmanager.log` from Settings → Troubleshooting would see a wall of poll-cycle spam drowning out real errors. Now logged at debug level so they only appear when users bump log level to debug.

• Mobile miner server defaults to `enabled: false` — fresh installs no longer auto-open port 8787 or trigger a Windows Firewall prompt for users who have no interest in mobile miners. The Settings → Mobile Miner Server toggle remains in place so users who want mobile support can opt in with one click. Existing installs with `mobile_server_config.json` already on disk are unaffected (this is intentional — no migration).

What this does NOT fix (deferred to v1.1 post-tester-feedback)

These are in the "nice to have" tier of the audit and intentionally left for after the first round of external feedback:

• Window size/position persistence (requires `tauri-plugin-window-state` dependency)
• Dead `src/pages/Miners.tsx` file (not imported anywhere, but deletion is scope creep)
• Config import/export
• Keyboard shortcuts
• Pools/Mobile Miners screenshots in `docs/screenshots/`
• Fleet Uptime (24h) hiding until 1h of samples collected
• Cargo.lock committing decision

Also deferred:

• Code signing — still the Certum Open Source Code Signing path after the repo goes public, ~$30/year, ~1-2 weeks for validation and token shipping. Tracked but not blocking v1.

Verification

• `npx tsc --noEmit` — clean, no errors, no output
• `cargo check` — clean, only 8 pre-existing dead-code warnings in `miner.rs` (unrelated to this change)
• Manual: clean install on a Windows machine without `%LOCALAPPDATA%\PoPManager\` → confirm welcome card renders with both CTAs
• Manual: click "Add ASIC Miner" CTA → verify routing to /miners and the Add Device panel opens cleanly
• Manual: click "Add Mobile Miner" CTA → verify routing to /mobile-miners (will show empty state since mobile server is now disabled by default)
• Manual: Settings → Mobile Miner Server → flip enable toggle → verify server starts, pairing code displays, firewall prompt appears
• Manual: force a remove operation to fail (e.g. by deleting the target device file while the modal is open) → verify inline error banner appears instead of native alert
• Manual: check `popmanager.log` after 5 minutes of normal polling → confirm no "Poll cycle start" lines at info level
• Manual: verify Settings → About shows the full supported hardware list

After merge: v1.0.0 release process

Once this lands, the v1 cut looks like:

1. Merge this PR
2. Flip repo to public on GitHub
3. `git tag v1.0.0 && git push --tags`
4. Build MSI via `npm run tauri build` on a clean Windows machine
5. Create GitHub release with the MSI attached
6. Upload a `latest.json` manifest pointing at the release asset so the in-app updater works
7. Do one clean-install smoke test on a second Windows machine before handing out the link
8. DM the first tester

Files changed

```
README.md | +43 -7
src-tauri/src/commands/mobile_miner.rs | +2 -2
src/pages/Dashboard.tsx | +45 -2
src/pages/MinerList.tsx | +9 -1
src/pages/MobileMinerDetail.tsx | +11 -3
src/pages/MobileMinerList.tsx | +23 -6
src/pages/Settings.tsx | +1 -1
7 files changed, 127 insertions(+), 29 deletions(-)
```