CANP-WP-0002 T07: semver precedence and strict packaging

Two defects from the original review of the seed.

Prerelease ordering was worse than first recorded. parse_semver returned
(major, minor, patch, raw_string), so 1.0.0-rc1 and 1.0.0 tied on the numeric
fields and then compared as strings — "1.0.0-rc1" > "1.0.0". A release
candidate therefore shadowed its own release for `newest` and for `>=`, not
just for the no-version case.

parse_semver now returns a SemVer section 11 precedence key: numeric fields, a
release/prerelease rank, then dot-separated prerelease identifiers with
numeric ones compared numerically. Build metadata is ignored. Beyond ordering,
prereleases are excluded from `any`, `newest` and `>=` entirely; only an exact
pin selects one, so publishing a release candidate never changes what existing
consumers resolve to. A package holding only prereleases now says so rather
than reporting a bare not-found.

Packaging copied the whole source directory, so a stray .git, virtualenv or
scratch file landed in the catalog and registry. Section 2 already required
otherwise — tools MUST ignore unknown non-reserved files unless a manifest
field references them — so this is conformance rather than a new rule. What is
new is that omissions are reported instead of silent:

  not packaged (not a reserved path, not referenced by the manifest): .git/, .venv/, notes.txt

LICENSE joins the reserved paths. Strict packaging would otherwise drop a
package's license text while faithfully copying its `license` field, which
contradicts section 14's instruction to surface licensing on publish and
install.

Spec: 2 (LICENSE, packaging obligation, reporting), 17.1 new, 10.3 note.

Reference CLI: parse_semver rewritten with is_prerelease; select_version and
pick_version updated; copy_package and report_skipped replace copy_immutable.
Tests 65 -> 78.

examples/pqrst-estimate carries a LICENSE and a license field, exercising the
new reserved path.

Also fixes a leaked loop variable in package_members that would have reported
a bad `template` path as an `evals` error.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Bjefh8NUiEiahN4JLwoSKM

Assistant: claude-code
Assistant-Model: opus
Assistant-Process: 388925@bnt-lap001
Assistant-Session: 3507023f-e0fd-4a1e-9d90-a0d4217d1502

reference/README.md

@@ -66,6 +66,12 @@ rather than resolved by guessing.
 - `{{ name }}` template substitution only.
 - No arbitrary expression/code execution.
 - Published versions are immutable by default.
+- `add`, `publish` and `install` copy only reserved paths and manifest-
+  referenced files. A working directory's `.git`, virtualenv or scratch files
+  never ship; whatever is left out is named on stderr.
+- Version precedence follows SemVer: a prerelease ranks below its release, and
+  `any`, `newest` and `>=` skip prereleases entirely. Only an exact pin
+  selects one.
 - `install` copies from registry to catalog.
 - `add` copies a package directly to catalog.
 - `search`, `show`, `resolve`, and `render` operate on catalog packages, and