0696 nwnss: document import audit policy

nwnss-audit.md

@@ -40,6 +40,52 @@ Current inventory summary:
 - `TEMP`: 2 files
 - Total listed files: 489
 
+
+## Audit policies
+
+### Header policy
+
+Header files imported from NSS should stay complete and close to the
+original source, even when many declarations are not used by the current
+`libnwnss` build yet.  Unused declarations are useful for later imports and
+should not be removed to hide compile errors.  Header changes are allowed
+only for concrete compile conflicts, include-path fixes, or narrowly scoped
+`MARS_NWE_NWNSS_USERSPACE` compatibility.  Prefer local `.c` compile fixes
+or private Mars compat headers over rewriting public NSS headers.
+
+### Source policy
+
+For `.c` and `sharedsrc/*.c.h` files, original NSS provenance is preferred.
+When a symbol is missing, search the complete NSS and nss-common source set,
+including `public_core/sharedsrc/*.c.h` and the original makefile wrapper
+pattern, before adding or keeping a Mars port.  Source code may be guarded for
+`MARS_NWE_NWNSS_USERSPACE` only where the original Linux kernel path can run
+in userspace without real kernel disk/block/VFS I/O.  Real disk/block/VFS I/O
+code stays in the tree but remains disabled in the default userspace build
+until it is ported to the Mars userspace I/O layer.
+
+### Port resolution workflow
+
+For every `PORT` entry below, audit in this order:
+
+1. Search the full NSS and nss-common sources for an original `.c` provider.
+2. Search `public_core/sharedsrc/*.c.h` and original makefiles for wrapper
+   patterns.
+3. If an original provider exists, replace or shrink the Mars port.
+4. If the provider is an external service not present in the shipped sources
+   (for example NEB/nebus), keep a clearly named Mars port with a comment
+   explaining the missing provenance and add/keep tests.
+5. If original files cannot be used for licensing reasons (for example the
+   Novell Unicode TAB tables), keep a clearly marked replacement with tests.
+6. Do not mark the file `AUDITED` until the provenance decision and test
+   coverage are recorded here.
+
+### Per-patch audit rule
+
+Future audit patches should include the source/header cleanup and the matching
+test changes in the same patch whenever behavior is affected.  Each patch must
+update this checklist for the files it verifies.
+
 ## 1. Currently audited or partially audited focus areas
 
 | Status | File / block | Kind | Test coverage | Notes |