fix: native module resolution breaks validation loop for ha:pdf (#111)

* fix: native module resolution breaks validation loop for ha:pdf

The module resolution loop checked only Object.keys(newSources) to
decide whether to continue resolving. Native modules (like ha:ziplib)
have no .js source — only module.json metadata — so the loop broke
early with valid=false and an empty errors array, producing the
cryptic 'Validation failed: •' message.

Root cause: ha:pdf imports ha:ziplib (native). The resolution loop
loaded ziplib.json but not ziplib.js (doesn't exist). Since
newSources was empty, it broke out of the loop before passing the
JSON metadata to the validator. The validator then couldn't confirm
ziplib was resolved, returning valid=false with no errors.

Fix: check all three sources (newSources, newModuleJsons, newDtsSources)
before deciding nothing was found. This allows native module metadata
to flow through and lets the validator recognise them as resolved.

Applied to both register_handler and register_module validation loops.

Signed-off-by: Simon Davies <simongdavies@users.noreply.github.com>

* fix: address PR #111 review feedback — clarify comment wording

- Changed 'no ha:/host: prefix' to 'missing ha: or host: prefix'
  to avoid confusion with the slash character
- Note: registerModuleImpl loop doesn't have the early-break pattern
  so it was never affected by the bug (commit message corrected)

Signed-off-by: Simon Davies <simongdavies@users.noreply.github.com>

---------

Signed-off-by: Simon Davies <simongdavies@users.noreply.github.com>

Author: simongdavies

src/agent/index.ts

@@ -1220,7 +1220,13 @@ async function validateHandlerCode(
       moduleJsons: newModuleJsons,
     } = loadModuleFilesForValidator(validation.missingSources, pluginManager);
 
-    if (Object.keys(newSources).length === 0) {
+    if (
+      Object.keys(newSources).length === 0 &&
+      Object.keys(newModuleJsons).length === 0 &&
+      Object.keys(newDtsSources).length === 0
+    ) {
+      // No new sources, module metadata, or type definitions found.
+      // Check if any specifiers are missing a ha: or host: prefix.
       const unresolvable = validation.missingSources.filter(
         (s) => !s.startsWith("ha:") && !s.startsWith("host:"),
       );
@@ -1401,7 +1407,12 @@ const registerHandlerTool = defineTool("register_handler", {
 
         // If we couldn't resolve ANY of the missing sources, generate helpful errors
         // This happens when imports use wrong prefixes (e.g., "pptx" instead of "ha:pptx")
-        if (Object.keys(newSources).length === 0) {
+        // Native modules have module.json but no .js source — check all three.
+        if (
+          Object.keys(newSources).length === 0 &&
+          Object.keys(newModuleJsons).length === 0 &&
+          Object.keys(newDtsSources).length === 0
+        ) {
           const unresolvable = validation.missingSources.filter(
             (s) => !s.startsWith("ha:") && !s.startsWith("host:"),
           );