Fix spec-explorer-data: pass metadata from SX routing instead of env lookup

The helper was trying to look up all-spec-items from get_component_env(),
but that only contains defcomp/defmacro — not regular defines. Now the
SX routing layer calls find-spec and passes filename/title/desc directly.

Also adds boundary declaration for spec-explorer-data.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

sx/sx/boundary.sx

@@ -109,3 +109,8 @@
   :params ()
   :returns "dict"
   :service "sx")
+
+(define-page-helper "spec-explorer-data"
+  :params (filename title desc)
+  :returns "dict"
+  :service "sx")

sx/sxc/pages/docs.sx

@@ -352,9 +352,15 @@
         :else (cond
           (starts-with? slug "explore/")
             (let ((spec-slug (slice slug 8 (string-length slug)))
-                  (data (spec-explorer-data spec-slug)))
-              (if data
-                (~spec-explorer-content :data data)
+                  (spec (find-spec spec-slug)))
+              (if spec
+                (let ((data (spec-explorer-data
+                              (get spec "filename")
+                              (get spec "title")
+                              (get spec "desc"))))
+                  (if data
+                    (~spec-explorer-content :data data)
+                    (~spec-not-found :slug spec-slug)))
                 (~spec-not-found :slug spec-slug)))
           :else (let ((spec (find-spec slug)))
             (if spec

sx/sxc/pages/helpers.py

@@ -142,9 +142,10 @@ def _read_spec_file(filename: str) -> str:
         return ";; spec file not found"
 
 
-def _spec_explorer_data(slug: str) -> dict | None:
+def _spec_explorer_data(filename: str, title: str = "", desc: str = "") -> dict | None:
     """Parse a spec file into structured metadata for the spec explorer.
 
+    Receives filename/title/desc from the SX routing layer (via find-spec).
     Returns sections with defines, effects, params, source, and translations.
     """
     import os
@@ -152,22 +153,9 @@ def _spec_explorer_data(slug: str) -> dict | None:
     from shared.sx.parser import parse_all
     from shared.sx.types import Symbol, Keyword
 
-    # Look up spec metadata from nav-data (via find-spec helper)
-    from shared.sx.jinja_bridge import get_component_env
-    env = get_component_env()
-    all_specs = env.get("all-spec-items", [])
-    spec_meta = None
-    for item in all_specs:
-        if isinstance(item, dict) and item.get("slug") == slug:
-            spec_meta = item
-            break
-    if not spec_meta:
+    if not filename:
         return None
 
-    filename = spec_meta.get("filename", "")
-    title = spec_meta.get("title", slug)
-    desc = spec_meta.get("desc", "")
-
     # Read the raw source
     ref_dir = os.path.join(os.path.dirname(__file__), "..", "..", "shared", "sx", "ref")
     if not os.path.isdir(ref_dir):
@@ -304,19 +292,6 @@ def _spec_explorer_data(slug: str) -> dict | None:
             i += 1
         return result
 
-    def _assign_to_section(line_num: int) -> dict:
-        """Find which section a line belongs to."""
-        best = sections[0]
-        for s in sections:
-            # Section starts at its first define or earlier
-            if s["defines"]:
-                first_line = s["defines"][0].get("line", 0)
-            else:
-                first_line = 0
-            # Use section order — defines after a section header belong to it
-        # Simple approach: find section by scanning source position
-        return best
-
     # Process defines
     all_defines: list[dict] = []
     py_emitter = None