fix(client): readable SMPValidationException on unparseable frame

[JPHutchins]

Summary

Improves SMP frame-parse failure diagnostics: when a response frame can't be parsed as the request's Response, ErrorV1, or ErrorV2, the client now raises a dedicated SMPValidationException carrying a readable summary + a hexdump and per-type Pydantic error breakdown — instead of the current code path, which is itself broken on main:

raise ValidationError(error_message)  # TypeError: __new__() missing 1 required positional argument: 'line_errors'

This revives @JaagupAverin's work from #88 / #91 (both unmerged; the codebase has since moved smpclient/ → src/smpclient/ and envr/black → uv/ruff), rebased onto current main with his authorship preserved.

Commits

1. chore: Cleanup validation error message. — authored by @JaagupAverin (cherry-picked, adapted to the src/ layout). The substantive fix + diagnostics.
2. refactor(client): functional cleanup of validation error diagnostics — applies project standards and the Jp/fix linter (ignore) #91 review:
   • Functional/immutable formatters (pure inner row() helpers over generators, no accumulator mutation).
   • Parse failures collected in an immutable tuple[type[Response], ValidationError] rather than dict[Type, ...] → resolves the Copilot mypy-invariance flag.
   • Fixes the stray trailing ) on each error line; corrects the misleading _hexdump docstring (no stdlib hexdump builtin).
   • pydantic_core.ErrorDetails typing; raise ... from None (per @JaagupAverin's suggestion).
   • Adds a regression test asserting the new exception type and its header/frame/per-type diagnostics.

Example output

Frame could not be parsed as any of:
	['ResetWriteResponse', 'OSManagementErrorV1', 'OSManagementErrorV2']
Header:
	Header(op=<OP.WRITE_RSP: 3>, version=<Version.V2: 1>, ... group_id=1, sequence=0, command_id=1)
Frame:
	0000  0b 00 00 06 00 01 00 01 a1 63 6f 66 66 00        .........coff.
Errors:
	Could not be parsed as ResetWriteResponse because 1 error(s):
		[extra_forbidden] Extra inputs are not permitted: off; input: 0
	...

Testing

• task lint (ruff + pydoclint) ✓
• task typecheck (mypy) ✓
• task test → 339 passed, 14 skipped (+1 new test)

Supersedes #91 and revives #88.

🤖 Generated with Claude Code

[Copilot]

Pull request overview

This PR improves SMP frame-parse failure diagnostics by introducing a dedicated SMPValidationException and emitting a readable summary plus detailed per-type Pydantic validation breakdown (including a hexdump) when a response frame can’t be parsed as the expected Response, ErrorV1, or ErrorV2.

Changes:

• Add SMPValidationException and raise it (instead of the currently broken ValidationError(...) path) when none of the candidate response types validate.
• Add formatting helpers to produce a hexdump and structured per-type Pydantic error detail output.
• Add a regression test asserting the new exception type and the presence of key diagnostics sections.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 2 comments.

File	Description
src/smpclient/__init__.py	Adds hexdump + validation error formatting helpers and raises/logs SMPValidationException when parsing fails for all response/error types.
src/smpclient/exceptions.py	Introduces the new SMPValidationException type carrying msg and details.
tests/test_smp_client.py	Adds a regression test ensuring an unparseable frame raises SMPValidationException and includes expected diagnostics content.

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.