build: rebuild when a project header changes

test-runner, test-repro-runner, test-runner-tsan, codebase-memory-mcp and
test-foundation are each built in a single compiler invocation from their
sources, and their rules listed only .c files as prerequisites. Editing a
header therefore changed nothing make could see, so the target was not
rebuilt and an incremental build silently kept testing the OLD header value.

Found while revert-checking the label-allowlist change in this branch: the
check passed, which was wrong. Shrinking CBM_SQL_TYPE_LIKE_LABELS should have
turned the pin test red and did not, because nothing had recompiled. Forcing a
rebuild produced the expected failure. A revert-check that cannot fail is worse
than no revert-check, because it reports confidence it did not earn.

This is the same class as the lsp_all.o staleness that #662 fixed with an
explicit dep list; that fix was per-object, this one covers the whole-program
targets.

PROJECT_HDRS globs src/, internal/cbm/ and tests/ headers and is added to the
five affected targets. Vendored trees are deliberately excluded: they are
pinned, they already carry explicit dep lists (LSP_UNITY_DEPS,
TS_RUNTIME_DEPS), and globbing tens of thousands of grammar headers would cost
more than it protects.

Verified: editing only src/foundation/constants.h, with no source file touched,
now rebuilds and turns the pin test red -- the exact edit that was invisible to
make before.

Signed-off-by: Martin Vogel <martin.vogel.tech@gmail.com>

Author: DeusData

Makefile.cbm

@@ -417,6 +417,19 @@ PROD_SRCS = $(FOUNDATION_SRCS) $(STORE_SRCS) $(CYPHER_SRCS) $(MCP_SRCS) $(DAEMON
 EXISTING_C_SRCS = $(EXTRACTION_SRCS) $(LSP_SRCS) $(TS_RUNTIME_SRC) \
                   $(GRAMMAR_SRCS) $(AC_LZ4_SRCS) $(ZSTD_SRCS) $(SQLITE_WRITER_SRC)
 
+# Project headers, as prerequisites for the targets built in one compiler
+# invocation from sources (test-runner, test-repro-runner, test-runner-tsan,
+# codebase-memory-mcp, test-foundation). Those rules list only .c files, so
+# editing a header changed nothing make could see and the target was NOT
+# rebuilt — an incremental build then silently tested the OLD header value.
+# Found while revert-checking a constants.h change: the check passed because
+# nothing had recompiled.
+#
+# Vendored trees are deliberately excluded — they are pinned, they carry their
+# own explicit dep lists (LSP_UNITY_DEPS, TS_RUNTIME_DEPS), and globbing tens of
+# thousands of grammar headers would cost more than it protects.
+PROJECT_HDRS = $(wildcard src/*.h src/*/*.h $(CBM_DIR)/*.h tests/*.h tests/repro/*.h)
+
 # ── Test sources ─────────────────────────────────────────────────
 
 TEST_FOUNDATION_SRCS = \
@@ -645,7 +658,7 @@ $(BUILD_DIR):
 
 # ── Foundation-only test (fast, no extraction) ───────────────────
 
-$(BUILD_DIR)/test-foundation: $(TEST_FOUNDATION_SRCS) $(FOUNDATION_SRCS) | $(BUILD_DIR)
+$(BUILD_DIR)/test-foundation: $(TEST_FOUNDATION_SRCS) $(FOUNDATION_SRCS) $(PROJECT_HDRS) | $(BUILD_DIR)
 	$(CC) $(CFLAGS_TEST) -o $@ $(TEST_FOUNDATION_SRCS) $(FOUNDATION_SRCS) $(LDFLAGS_TEST)
 
 test-foundation: $(BUILD_DIR)/test-foundation
@@ -761,7 +774,7 @@ $(UNIXCODER_OBJ): $(UNIXCODER_BLOB_SRC) vendored/nomic/code_vectors.bin | $(BUIL
 OBJS_VENDORED_TEST = $(MIMALLOC_OBJ_TEST) $(SQLITE3_OBJ_TEST) $(TRE_OBJ_TEST) $(GRAMMAR_OBJS_TEST) $(TS_RUNTIME_OBJ_TEST) $(LSP_OBJ_TEST) $(PP_OBJ_TEST) $(LZ4_OBJ_TEST) $(ZSTD_OBJ_TEST) $(UNIXCODER_OBJ)
 OBJS_VENDORED_TSAN = $(MIMALLOC_OBJ_TSAN) $(SQLITE3_OBJ_TSAN) $(TRE_OBJ_TSAN) $(GRAMMAR_OBJS_TSAN) $(TS_RUNTIME_OBJ_TSAN) $(LSP_OBJ_TSAN) $(PP_OBJ_TSAN) $(LZ4_OBJ_TSAN) $(ZSTD_OBJ_TSAN) $(UNIXCODER_OBJ)
 
-$(BUILD_DIR)/test-runner: $(ALL_TEST_SRCS) $(PROD_SRCS) $(EXTRACTION_SRCS) $(AC_LZ4_SRCS) $(ZSTD_SRCS) $(SQLITE_WRITER_SRC) $(OBJS_VENDORED_TEST) | $(BUILD_DIR)
+$(BUILD_DIR)/test-runner: $(ALL_TEST_SRCS) $(PROD_SRCS) $(EXTRACTION_SRCS) $(AC_LZ4_SRCS) $(ZSTD_SRCS) $(SQLITE_WRITER_SRC) $(OBJS_VENDORED_TEST) $(PROJECT_HDRS) | $(BUILD_DIR)
 	$(CC) $(CFLAGS_TEST) -Itests -Itests/repro -o $@ \
 		$(ALL_TEST_SRCS) $(PROD_SRCS) \
 		$(EXTRACTION_SRCS) $(AC_LZ4_SRCS) $(ZSTD_SRCS) $(SQLITE_WRITER_SRC) \
@@ -789,7 +802,7 @@ test-focused: $(BUILD_DIR)/test-runner
 # Mirrors test-runner's link line but uses repro_main.c (own main + counters)
 # and TEST_REPRO_SRCS instead of ALL_TEST_SRCS. Exits non-zero while any bug is
 # still reproduced (the expected state); bug-repro.yml surfaces it as a board.
-$(BUILD_DIR)/test-repro-runner: $(TEST_REPRO_SRCS) $(PROD_SRCS) $(EXTRACTION_SRCS) $(AC_LZ4_SRCS) $(ZSTD_SRCS) $(SQLITE_WRITER_SRC) $(OBJS_VENDORED_TEST) | $(BUILD_DIR)
+$(BUILD_DIR)/test-repro-runner: $(TEST_REPRO_SRCS) $(PROD_SRCS) $(EXTRACTION_SRCS) $(AC_LZ4_SRCS) $(ZSTD_SRCS) $(SQLITE_WRITER_SRC) $(OBJS_VENDORED_TEST) $(PROJECT_HDRS) | $(BUILD_DIR)
 	$(CC) $(CFLAGS_TEST) -Itests -o $@ \
 		$(TEST_REPRO_SRCS) $(PROD_SRCS) \
 		$(EXTRACTION_SRCS) $(AC_LZ4_SRCS) $(ZSTD_SRCS) $(SQLITE_WRITER_SRC) \
@@ -831,7 +844,7 @@ TSAN_OPTIONS ?= halt_on_error=1
 # Normal ASan/native/soak paths remain uncapped. High-worker TSan diagnostics
 # invoke test-runner-tsan directly so release gates cannot drift accidentally.
 
-$(BUILD_DIR)/test-runner-tsan: $(ALL_TEST_SRCS) $(PROD_SRCS) $(EXTRACTION_SRCS) $(AC_LZ4_SRCS) $(ZSTD_SRCS) $(SQLITE_WRITER_SRC) $(OBJS_VENDORED_TSAN) | $(BUILD_DIR)
+$(BUILD_DIR)/test-runner-tsan: $(ALL_TEST_SRCS) $(PROD_SRCS) $(EXTRACTION_SRCS) $(AC_LZ4_SRCS) $(ZSTD_SRCS) $(SQLITE_WRITER_SRC) $(OBJS_VENDORED_TSAN) $(PROJECT_HDRS) | $(BUILD_DIR)
 	$(CC) $(CFLAGS_TSAN) -Itests -Itests/repro -o $@ \
 		$(ALL_TEST_SRCS) $(PROD_SRCS) \
 		$(EXTRACTION_SRCS) $(AC_LZ4_SRCS) $(ZSTD_SRCS) $(SQLITE_WRITER_SRC) \
@@ -904,7 +917,7 @@ $(BUILD_DIR)/.build-config: build-config-check | $(BUILD_DIR)
 	else mv -f $@.tmp $@; rm -f $(BUILD_DIR)/codebase-memory-mcp; \
 	echo "=== build config changed -> full rebuild: $(BUILD_CONFIG_SIG) ==="; fi
 
-$(BUILD_DIR)/codebase-memory-mcp: $(MAIN_SRC) $(PROD_SRCS) $(EXTRACTION_SRCS) $(AC_LZ4_SRCS) $(ZSTD_SRCS) $(SQLITE_WRITER_SRC) $(OBJS_VENDORED_PROD) $(BUILD_DIR)/.build-config | $(BUILD_DIR)
+$(BUILD_DIR)/codebase-memory-mcp: $(MAIN_SRC) $(PROD_SRCS) $(EXTRACTION_SRCS) $(AC_LZ4_SRCS) $(ZSTD_SRCS) $(SQLITE_WRITER_SRC) $(OBJS_VENDORED_PROD) $(BUILD_DIR)/.build-config $(PROJECT_HDRS) | $(BUILD_DIR)
 	$(CC) $(CFLAGS_PROD) -o $@ \
 		$(MAIN_SRC) $(PROD_SRCS) \
 		$(EXTRACTION_SRCS) $(AC_LZ4_SRCS) $(ZSTD_SRCS) $(SQLITE_WRITER_SRC) \