Add native audio/image efferent surfaces + projector proof-of-shape

audio-surface.el / image-surface.el: own-core additive-synthesis WAV and
raster-PNG renderers (integer-only DSP, since EL has no floats), rendered
from learned engram signatures via a pluggable surface-profile
abstraction (surface-profile.el). audio-demo.el / image-demo.el are
drivers. NOTE: demo files hardcode absolute paths to this worktree's own
directory — will need a path fixup before landing.

elp/projector/ is a Python package the author's own README marks as
"STAGING/PROOF-OF-SHAPE — not the deliverable", superseded by the native
.el surface-profile work above; kept as a validated architecture proof.
Generated output (elp/faculty/{out,sig}, elp/projector/out,
__pycache__) intentionally excluded.

elp/projector/provenance.py

@@ -0,0 +1,63 @@
+"""provenance.py — the faithfulness audit + geometry->section trace.
+
+A document projected from geometry is only worth anything if every claim traces
+back. This module walks the DocumentIR and proves the discipline held:
+
+  * ZERO ungrounded claims (every fact/interpretation has a real node id),
+  * every emitted sentence maps to a geometry edge (or is a marked connective),
+  * SACRED polarity survived (negations are reported, never silently dropped),
+  * COHERE introduced no new geometry (connectives carry no claim).
+
+It emits both a machine verdict and a human-readable geometry->section table.
+"""
+from __future__ import annotations
+
+from document_ir import DocumentIR
+
+
+def audit(doc: DocumentIR) -> dict:
+    provs = doc.all_provenance()
+    facts = [p for p in provs if p.kind in ("fact", "interpretation")]
+    connectives = [p for p in provs if p.kind == "connective"]
+    ungrounded = [p for p in facts if not p.node_id]
+    negations = [p for p in facts if p.polarity == "neg"]
+    node_ids = sorted({p.node_id for p in facts if p.node_id})
+    return {
+        "claims": len(facts),
+        "connectives": len(connectives),
+        "ungrounded_claims": len(ungrounded),
+        "negations_preserved": len(negations),
+        "distinct_source_nodes": len(node_ids),
+        "faithful": len(ungrounded) == 0,
+        "source_nodes": node_ids,
+    }
+
+
+def trace_table(doc: DocumentIR) -> str:
+    """Human-readable geometry -> section -> claim provenance table."""
+    lines = ["# Provenance — every claim traces geometry", ""]
+    lines.append(f"**Document:** {doc.title}")
+    a = audit(doc)
+    lines.append(f"**Claims:** {a['claims']}  ·  **Ungrounded:** "
+                 f"{a['ungrounded_claims']}  ·  **Negations preserved:** "
+                 f"{a['negations_preserved']}  ·  **Source nodes:** "
+                 f"{a['distinct_source_nodes']}  ·  **Faithful:** "
+                 f"{'YES' if a['faithful'] else 'NO'}")
+    lines.append("")
+    for si, sec in enumerate(doc.sections, 1):
+        lines.append(f"## {si}. {sec.heading}")
+        lines.append(f"_seed nodes: {', '.join(i[:8] for i in sec.seed_ids)}_")
+        lines.append("")
+        lines.append("| # | realized claim | traces geometry edge |")
+        lines.append("|---|----------------|----------------------|")
+        n = 0
+        for block in sec.blocks:
+            for sent, prov in zip(block.sentences, block.provenance):
+                if prov.kind == "connective":
+                    continue
+                n += 1
+                edge = prov.trace().replace("|", "\\|")
+                s = sent.replace("|", "\\|")
+                lines.append(f"| {n} | {s} | {edge} |")
+        lines.append("")
+    return "\n".join(lines) + "\n"