feat: validate uv workspace members/excludes and discover parent workspaces (Fixes #290) (#352)

Addresses the TODO items in `pet-uv` for workspace member/exclude
validation.

## Changes

- Parse `[tool.uv.workspace]` `members` and `exclude` fields instead of
using `IgnoredAny`
- Add `is_workspace_member()` with glob pattern matching (using
`require_literal_separator` so `*` doesn't cross directory boundaries)
- Walk up parent directories via `find_workspace_for_project()` to
discover workspace roots
- Stop at the first workspace found — if the project isn't a member of
it, it's not part of any workspace
- Add `glob` dependency to `pet-uv`
- 9 new tests covering member matching, exclusion, implicit members,
parent discovery, and deserialization

Fixes #290

cc @zsol — would appreciate your input since you authored the original
`pet-uv` workspace support in #263.

Author: karthiknadig

Cargo.lock

@@ -10,6 +10,7 @@ pet-python-utils = { path = "../pet-python-utils" }
 serde = {version = "1.0.226", features = ["derive"]}
 toml = "0.9.7"
 log = "0.4.21"
+glob = "0.3.1"
 
 [dev-dependencies]
 tempfile = "3.13"