fix(pfs): since = earliest evidence; derived families get no synonyms (refs F3 F5)

`since` used to take cpt_since unconditionally, so a code first ingested
in the 2019 CPT edition read `since=2019` even when the RVU/FR record
shows it created years earlier (99490, CY2015). Now `since =
min(cpt_since, appeared-event year)` when an appeared event exists —
cpt_since is only the earliest *ingested* edition, not proof the code
didn't exist before that.

Derived (non-hand) families used to get `(key.lower(), name.lower())`
as synonyms, turning ~1,334 one/two-word CPT heading names ("Repair",
"Excision") into chat triggers and costing detect_codes 0.50s/call at
8.5k families. Derived families now get an empty synonym tuple; hand
families are unaffected. Matching a derived family by name is #699's
job (a precompiled alternation).

src/pfs/families.py

@@ -377,7 +377,16 @@ def _group_rows(
         else:
             role = "base"
         if c in cpt_since:
-            since = cpt_since[c]
+            appeared = next((ev.year for ev in evs if ev.kind == "appeared"), None)
+            # C13: cpt_since is only the earliest edition *on hand* — it
+            # is not evidence the code didn't exist earlier. When an
+            # RVU/FR "appeared" event is older, that's the real origin
+            # (e.g. 99490 created CY2015, first ingested CPT edition
+            # 2019); when no such event exists, cpt_since is the only
+            # evidence there is.
+            since = (
+                min(cpt_since[c], appeared) if appeared is not None else cpt_since[c]
+            )
             until = (
                 None
                 if newest_cpt_year is not None and cpt_last_year[c] >= newest_cpt_year
@@ -752,11 +761,14 @@ def load_families(con: Any) -> dict[str, Family]:
     for r in rows:
         fam = out.get(r.key)
         codes = (*(fam.codes if fam else ()), r.code)
-        syn = (
+        # Ruling F3: a derived (non-hand) family gets no synonyms at all
-            HAND_FAMILIES[r.key].synonyms
+        # — one/two-word CPT heading names ("Repair", "Excision") would
-            if r.key in HAND_FAMILIES
+        # otherwise become chat triggers across ~1,334 derived families,
-            else (r.key.lower(), r.name.lower())
+        # and scanning every family's synonyms against every chunk costs
-        )
+        # 0.50s/call at ~8.5k families. Matching a derived family by name
+        # is #699's job (a precompiled alternation), not this one. Hand
+        # families keep their curated synonyms.
+        syn = HAND_FAMILIES[r.key].synonyms if r.key in HAND_FAMILIES else ()
         out[r.key] = Family(r.key, r.name, tuple(sorted(set(codes))), syn)
     return out
 

tests/pfs/test_families.py

@@ -1025,6 +1025,63 @@ class TestCptPresenceC12:
         assert by_code["90001"].until is None
 
 
+class TestSinceEarliestEvidenceC13:
+    """F5 / Ruling C13: ``since`` = min(cpt_since, appeared-event year)
+    when an ``appeared`` event exists — cpt_since is only the earliest
+    *ingested* edition, not evidence the code didn't exist earlier."""
+
+    def test_since_is_min_of_cpt_presence_and_appeared_event(self):
+        # 99490 was created CY2015 but the oldest CPT edition on hand is
+        # 2019 — since must read 2015, not 2019.
+        sections = [_cpt_section("sec_a", ("Chapter", "Heading A"))]
+        cpt_codes = [_cpt_code("99490", "sec_a", year=2024)]
+        cpt_presence = {"99490": (2019, 2021, 2022, 2024)}
+        events = {"99490": [_ev("99490", 2015, "appeared")]}
+        rows = derive_families(
+            {},
+            events,
+            {},
+            cpt_codes=cpt_codes,
+            cpt_sections=sections,
+            cpt_presence=cpt_presence,
+        )
+        by_code = {r.code: r for r in rows}
+        assert by_code["99490"].since == 2015
+
+    def test_since_falls_back_to_cpt_presence_when_no_appeared_event(self):
+        sections = [_cpt_section("sec_a", ("Chapter", "Heading A"))]
+        cpt_codes = [_cpt_code("90001", "sec_a", year=2024)]
+        cpt_presence = {"90001": (2019, 2021, 2022, 2024)}
+        rows = derive_families(
+            {},
+            {},
+            {},
+            cpt_codes=cpt_codes,
+            cpt_sections=sections,
+            cpt_presence=cpt_presence,
+        )
+        by_code = {r.code: r for r in rows}
+        assert by_code["90001"].since == 2019
+
+    def test_since_keeps_cpt_presence_when_appeared_event_is_later(self):
+        # An appeared event newer than the CPT evidence must not win —
+        # min(), not "prefer the event".
+        sections = [_cpt_section("sec_a", ("Chapter", "Heading A"))]
+        cpt_codes = [_cpt_code("90001", "sec_a", year=2024)]
+        cpt_presence = {"90001": (2019, 2021, 2022, 2024)}
+        events = {"90001": [_ev("90001", 2021, "appeared")]}
+        rows = derive_families(
+            {},
+            events,
+            {},
+            cpt_codes=cpt_codes,
+            cpt_sections=sections,
+            cpt_presence=cpt_presence,
+        )
+        by_code = {r.code: r for r in rows}
+        assert by_code["90001"].since == 2019
+
+
 class TestLoadAndRefresh:
     def test_load_and_refresh_in_place(self, restore_families):
         mod = restore_families
@@ -1099,6 +1156,59 @@ class TestLoadAndRefresh:
         finally:
             con.close()
 
+    def test_derived_family_gets_empty_synonyms(self, restore_families):
+        # F3: a derived (non-hand) family must not become a chat trigger
+        # off its own one/two-word name — matching by name is #699's job.
+        mod = restore_families
+        con = duckdb.connect(":memory:")
+        try:
+            ensure_tables(con)
+            write_families(
+                con,
+                [
+                    FamilyRow(
+                        "AORTA-REPAIR",
+                        "Repair",
+                        "99999",
+                        "base",
+                        None,
+                        None,
+                        "",
+                        0,
+                    )
+                ],
+            )
+            refresh_from(con)
+            assert mod.FAMILIES["AORTA-REPAIR"].synonyms == ()
+            assert detect_codes("repair of the aorta").families == ()
+        finally:
+            con.close()
+
+    def test_hand_family_keeps_its_synonyms_after_refresh(self, restore_families):
+        mod = restore_families
+        con = duckdb.connect(":memory:")
+        try:
+            ensure_tables(con)
+            write_families(
+                con,
+                [
+                    FamilyRow(
+                        "CCM",
+                        "Chronic Care Management",
+                        "99490",
+                        "base",
+                        None,
+                        None,
+                        "",
+                        0,
+                    )
+                ],
+            )
+            refresh_from(con)
+            assert mod.FAMILIES["CCM"].synonyms == HAND_FAMILIES["CCM"].synonyms
+        finally:
+            con.close()
+
     def test_schema_present_table_absent_returns_empty(self):
         # pfs schema created (e.g. by an earlier ensure_tables call for a
         # sibling table) but pfs.code_family itself never materialized —