Fix Machine API CI

[JordanNoone]

Fix the dependency/API mismatches blocking compilation, select Bambu’s Rustls provider explicitly, and resolve the Clippy errors by boxing oversized payloads and removing redundant borrows/map keys.

Refs #422; incorporates the dependency bumps from #392 and #377. Boxed enum payloads change Rust construction types; JSON fields and the status getter’s return type stay unchanged.

At 16613b0, build, all 42 tests, Clippy, formatting and security pass. Codecov remains red: 20.05% versus a February 2025 baseline, 101 commits behind main. Coverage policy is unchanged. Printer connectivity and telemetry delivery remain unverified.

[codecov]

Codecov Report

❌ Patch coverage is 5.00000% with 19 lines in your changes missing coverage. Please review.
✅ Project coverage is 20.05%. Comparing base (1550a39) to head (16613b0).
⚠️ Report is 101 commits behind head on main.

Files with missing lines	Patch %	Lines
bambulabs/src/client.rs	0.00%	9 Missing ⚠️
src/bin/machine-api/cmd_serve.rs	0.00%	3 Missing ⚠️
src/bin/machine-api/main.rs	0.00%	3 Missing ⚠️
src/server/endpoints.rs	0.00%	2 Missing ⚠️
src/server/mod.rs	33.33%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #423      +/-   ##
==========================================
- Coverage   24.14%   20.05%   -4.10%     
==========================================
  Files          46       44       -2     
  Lines        3164     2698     -466     
==========================================
- Hits          764      541     -223     
+ Misses       2400     2157     -243     

Flag	Coverage Δ
unittests	20.05% <5.00%> (-4.10%)	⬇️

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