io: improve APDU handling

[jarevalo-ledger]

Description

Improve APDU handling.

Changes include

• Bugfix (non-breaking change that solves an issue)
• New feature (non-breaking change that adds functionality)
• Breaking change (change that is not backwards-compatible and/or changes current functionality)
• Tests
• Documentation
• Other (for changes that might not fit in any category)

Breaking changes

Please complete this section if any breaking changes have been made, otherwise delete it.

Additional comments

Please post additional comments in this section if you have them, otherwise delete it.

Auto cherry-pick in API_LEVEL

If requested to port the commits from this PR on a dedicated API_LEVEL branch,
select the targeted one(s), or add new references if not listed:

[ ] TARGET_API_LEVEL: API_LEVEL_26
[ ] TARGET_API_LEVEL: API_LEVEL_27

This will only create the PR with cherry-picks, ready to be reviewed and merged.

Remember:

• The merge will ALWAYS be a manual operation.
• It is possible the cherry-picks don't apply correctly, mainly if previous commits have been forgotten.
• In case of failure, there is no other solution than redo the operation manually...

[codecov-commenter]

Codecov Report

❌ Patch coverage is 0% with 22 lines in your changes missing coverage. Please review.
✅ Project coverage is 36.23%. Comparing base (149bc18) to head (6aea963).

Files with missing lines	Patch %	Lines
io/src/os_io.c	0.00%	22 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #1701      +/-   ##
==========================================
- Coverage   39.66%   36.23%   -3.44%     
==========================================
  Files         239      239              
  Lines       23196    23218      +22     
  Branches     4622     4635      +13     
==========================================
- Hits         9201     8413     -788     
- Misses      13485    14225     +740     
- Partials      510      580      +70     

Flag	Coverage Δ
fuzzing	18.07% <0.00%> (-6.07%)	⬇️
unittests	89.51% <ø> (ø)

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[github-actions]

Code coverage report

Per-file coverage

Package	Line Rate	Branch Rate	Health
include	93%	50%	✔
lib_cxng.include	100%	0%	✔
lib_tlv	92%	80%	✔
lib_tlv.use_cases	91%	76%	✔
.........tmp.cmake-fetch-deps.cmock-src.src	45%	34%	❌
.........tmp.cmake-fetch-deps.unity-src.src	13%	7%	❌
lib_alloc	94%	81%	✔
.........tmp.cmake-fetch-deps.cmock-src.src	40%	28%	❌
.........tmp.cmake-fetch-deps.unity-src.src	13%	7%	❌
lib_lists	94%	73%	✔
.........tmp.cmake-fetch-deps.cmock-src.src	0%	0%	❌
.........tmp.cmake-fetch-deps.unity-src.src	10%	3%	❌
lib_standard_app	89%	81%	✔
.........tmp.cmake-fetch-deps.cmock-src.src	0%	0%	❌
.........tmp.cmake-fetch-deps.unity-src.src	13%	7%	❌
lib_standard_app	100%	87%	✔
.........tmp.cmake-fetch-deps.cmock-src.src	16%	5%	❌
.........tmp.cmake-fetch-deps.unity-src.src	12%	6%	❌
src	68%	60%	➖
.........tmp.cmake-fetch-deps.cmock-src.src	16%	5%	❌
.........tmp.cmake-fetch-deps.unity-src.src	11%	5%	❌
.........usr.include	100%	0%	✔
app_features.address_book.src	88%	73%	✔
include	100%	0%	✔
lib_standard_app	20%	27%	❌
lib_tlv	72%	52%	➖
.........tmp.cmake-fetch-deps.cmock-src.src	44%	33%	❌
.........tmp.cmake-fetch-deps.unity-src.src	14%	8%	❌
Summary	33% (3448 / 9622)	23% (1534 / 6222)	❌

[sportron-ledger]

Should be G_io_tx_buffer as done in os_io_handle_ux_event_reject_apdu function.