feat: hydrate headless system root and modernize db format

[jsavin]

Summary

• add and backup tracking helpers so legacy roots can auto-migrate to v7
• wire frontier-cli and optional hydration path to load tables, create missing subtables, and run scripts headless
• refresh headless/test scaffolding + docs to reflect the new system root flow and expectations

Testing

• make -C tests runtime_tests
• tests/runtime_tests
• make -C tests db_format_tests

[chatgpt-codex-connector]

💡 Codex Review

Frontier/tests/headless_table_stubs.c

Lines 89 to 126 in 3fc4635

	boolean tableverbnew (hdlexternalvariable *hvariable) {
	hdltablevariable hv;
	hdlhashtable ht;
	if (!langnewexternalvariable(true, 0L, (hdlexternalvariable *)&hv))
	return false;
	if (!newhashtable(&ht)) {
	disposehandle((Handle)hv);
	return false;
	}
	(**hv).variabledata = (long) ht;
	(**ht).hashtablerefcon = (long) hv;
	(**ht).fldirty = true;
	*hvariable = (hdlexternalvariable) hv;
	return true;
	}
	boolean tableverbpack (hdlexternalvariable h, Handle *hpacked, boolean *flnewdbaddress) {
	(void) h;
	if (hpacked)
	*hpacked = nil;
	if (flnewdbaddress)
	*flnewdbaddress = false;
	return false;
	}
	boolean tableverbpacktotext (hdlexternalvariable h, Handle htext) {
	(void) h;
	(void) htext;
	return false;
	}
	boolean tableverbunpack (Handle hpacked, long *ixload, hdlexternalvariable *h, boolean fldisk) {
	(void) hpacked;
	(void) ixload;
	(void) h;
	(void) fldisk;
	return false;
	}

Disable table stubs when linking real tablepack

The CLI Makefile now compiles Common/source/tablepack.c and defines HEADLESS_USE_REAL_TABLEPACK, but tests/headless_table_stubs.c still always provides stub implementations for tableverbpack, tableverbpacktotext, tableverbunpack, etc. Building the CLI with both files will either fail at link time due to multiple definitions of these symbols or, depending on link order, the stubbed functions will override the real ones and always return false, causing hydration and table persistence to break. These stubs need to be compiled out when HEADLESS_USE_REAL_TABLEPACK is set (e.g., wrap the remaining functions in an #ifndef HEADLESS_USE_REAL_TABLEPACK).

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[jsavin]

@codex review

[chatgpt-codex-connector]

Codex Review: Didn't find any major issues. What shall we delve into next?

ℹ️ About Codex in GitHub

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• Open a pull request for review
• Mark a draft as ready
• Comment "@codex review".

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