Foundation for replacing the single embedded defaults.zddc.yaml with a
.zddc.zip policy SUBTREE mountable at any directory. defaults.zddc.yaml stays
live and authoritative for now — this is purely additive.
Phase 1 — author the per-depth default tree under internal/zddc/defaults/, one
focused .zddc per canonical folder (root, */, */archive, */working[/*], */ssr,
*/mdl[/*], */rsk[/*], */staging[/*], */reviewing[/*], */incoming[/*]). The
`_any_` directory is the on-disk stand-in for the "*" wildcard, so the repo
holds no shell-/go:embed-hostile literal "*" directories.
Phase 2 — PolicyTree (internal/zddc/zippolicy.go): a set of .zddc documents
keyed by member dir relative to a mount point, with "*" wildcards.
resolveTreeDir does literal-first, most-specific segment matching (mirrors the
paths: cascade); Along returns the governing member at each cascade level
root→leaf; LoadPolicyTreeFromDir loads the source tree (mapping _any_ → *).
This is the engine for "drop a .zddc.zip at any level"; inherit:false in a
resolved member makes that subtree a self-contained island (existing fence
mechanism, unchanged).
Tests: resolver matching mechanics; the split tree loads with the expected keys
+ content (data-level faithfulness — full effective-policy parity is the
Layer-2 matrix once the cascade is wired in Phase 4); Along ordering.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>