mAi: #95 - t-paliad-264 - fix de.inf.lg Replik/Duplik sequencing

Replik and Duplik had parent_id = NULL with a 4-week placeholder
duration, so the projection anchored both off the proceeding's
trigger date (Klageerhebung) - both rows rendered at the same
calendar date AND before Klageerwiderung.

Migration 124 anchors Replik on Klageerwiderung
(de.inf.lg.erwidg) and Duplik on Replik, and marks both
is_court_set = true with legal_source DE.ZPO.273. The 4-week
placeholder duration is retained so the timeline gives a sane
notional date for each row; the lawyer overrides it with "Datum
setzen" once the court issues the actual period.

Each UPDATE is guarded by parent_id IS NULL so a re-apply against
a DB that already carries the fix no-ops cleanly (mig 095
convention). No new audit-log rows on idempotent re-runs.

Slot note: originally landed as 123 in an earlier iteration;
cronus's t-paliad-246 Backup-Mode migration won slot 123 in the
parallel merge race, so this migration shifted to slot 124.

ZPO citations in the migration comment per the t-paliad-264 brief:
  - Klageerhebung           - section 253 ZPO
  - Anzeige Verteidigungsbereitschaft - section 276 Abs. 1 S. 1 ZPO
  - Klageerwiderung         - section 276 Abs. 1 S. 2 + section 277 ZPO
  - Replik / Duplik         - vom Gericht bestimmte Frist
    (section 273 ZPO Anordnungskompetenz; section 282 ZPO
    prozessuale Foerderungspflicht)

Verified ordering for trigger 2026-05-25:
  Klage         2026-05-25 Mon
  Anzeige       2026-06-08 Mon
  Klageerwidg   2026-07-06 Mon
  Replik        2026-08-03 Mon
  Duplik        2026-08-31 Mon

Each row strictly later than the previous; Replik and Duplik no
longer collide on the same date and no longer precede the
Klageerwiderung.

internal/db/migrations/124_de_inf_lg_replik_duplik_sequencing.down.sql

@@ -0,0 +1,31 @@
+-- Revert t-paliad-264 / m/paliad#95.
+-- Restores Replik and Duplik to parent_id = NULL with the pre-fix
+-- "Frist vom Gericht bestimmt" placeholder note. The pre-fix rows
+-- carried legal_source = NULL and is_court_set = false; both
+-- placeholder durations (4 weeks) are left untouched (the .up
+-- migration did not modify them).
+--
+-- audit_reason set_config required for the mig 079 trigger.
+
+SELECT set_config(
+    'paliad.audit_reason',
+    'mig 124 revert: unwind de.inf.lg Replik/Duplik sequencing back to pre-#95 placeholder state',
+    true);
+
+UPDATE paliad.deadline_rules
+SET parent_id      = NULL,
+    is_court_set   = false,
+    legal_source   = NULL,
+    deadline_notes = 'Frist vom Gericht bestimmt',
+    deadline_notes_en = NULL
+WHERE submission_code = 'de.inf.lg.replik'
+  AND is_active = true;
+
+UPDATE paliad.deadline_rules
+SET parent_id      = NULL,
+    is_court_set   = false,
+    legal_source   = NULL,
+    deadline_notes = 'Frist vom Gericht bestimmt',
+    deadline_notes_en = NULL
+WHERE submission_code = 'de.inf.lg.duplik'
+  AND is_active = true;

internal/db/migrations/124_de_inf_lg_replik_duplik_sequencing.up.sql

@@ -0,0 +1,94 @@
+-- t-paliad-264 / m/paliad#95 — Fix de.inf.lg Replik + Duplik sequencing.
+--
+-- BEFORE this migration, the de.inf.lg rules for Replik and Duplik
+-- had parent_id = NULL with duration_value = 4 weeks each. The
+-- projection therefore anchored both off the proceeding's trigger
+-- date (Klageerhebung) and added 4 weeks → both rows rendered at the
+-- same calendar date, BEFORE Klageerwiderung (which sits at
+-- Klageerhebung + 6 weeks per § 276 Abs. 1 S. 2 ZPO).
+--
+-- Correct ZPO sequence for first-instance infringement before the
+-- Landgericht is:
+--
+--   Klageerhebung (§ 253 ZPO)
+--     → Anzeige der Verteidigungsbereitschaft (§ 276 Abs. 1 S. 1 ZPO,
+--       2 Wochen ab Zustellung der Klage)
+--     → Klageerwiderung (§ 276 Abs. 1 S. 2 + § 277 ZPO; vom Gericht
+--       gesetzte Frist von mindestens 2 Wochen, in der Praxis 6 Wochen)
+--     → Replik (vom Gericht gesetzte Frist; Anordnungskompetenz aus
+--       § 273 ZPO, prozessuale Förderungspflicht der Parteien aus
+--       § 282 ZPO; in der Praxis ~ 4 Wochen ab Zustellung der
+--       Klageerwiderung)
+--     → Duplik (vom Gericht gesetzte Frist; § 273, § 282 ZPO; in der
+--       Praxis ~ 4 Wochen ab Zustellung der Replik)
+--
+-- Replik and Duplik have NO statutory period — the Landgericht fixes
+-- the period in its prozessleitende Verfügung. We model them as
+-- is_court_set = true with a placeholder 4-week duration anchored on
+-- the immediately preceding filing so the timeline (a) renders them
+-- in strict chronological order and (b) gives the lawyer a sane
+-- notional date that can be overridden via "Datum setzen" once the
+-- court issues the actual period.
+--
+-- legal_source set to DE.ZPO.273 (Vorbereitung des Termins —
+-- court's case-management power that authorises setting Replik /
+-- Duplik periods). The full citation chain (§§ 273, 282 ZPO) lives
+-- in deadline_notes so the rendered card explains the source.
+--
+-- Scope strictly de.inf.lg / cfi per the t-paliad-264 brief. Other
+-- jurisdictions are out of scope and will be addressed via curie's
+-- m/paliad#94 audit follow-ups (Wave 0+).
+--
+-- Slot note: this migration originally landed as 123 in an earlier
+-- iteration; cronus's t-paliad-246 Backup-Mode migration won slot
+-- 123 in parallel-merge order, so this one shifted to 124.
+--
+-- Idempotency: each UPDATE is guarded by a WHERE clause that only
+-- matches the pre-fix row state (parent_id IS NULL on Replik /
+-- Duplik, since that was the load-bearing bug). A re-apply against
+-- a DB that already carries the fix matches zero rows and no-ops —
+-- no duplicate audit-log rows in paliad.deadline_rule_audit, no
+-- redundant writes. Mig 095 convention.
+--
+-- audit_reason set_config required at the top — the mig 079 trigger
+-- on paliad.deadline_rules raises EXCEPTION 'audit reason required'
+-- on any UPDATE without it.
+
+SELECT set_config(
+    'paliad.audit_reason',
+    'mig 124: t-paliad-264 / m/paliad#95 — anchor de.inf.lg Replik on Klageerwiderung and Duplik on Replik, mark both is_court_set per § 273 ZPO',
+    true);
+
+-- Replik anchors on Klageerwiderung (de.inf.lg.erwidg).
+-- Guard: parent_id IS NULL — only fires against the pre-fix shape.
+UPDATE paliad.deadline_rules
+SET parent_id = (
+        SELECT id FROM paliad.deadline_rules
+        WHERE submission_code = 'de.inf.lg.erwidg'
+          AND is_active = true
+        LIMIT 1
+    ),
+    is_court_set   = true,
+    legal_source   = 'DE.ZPO.273',
+    deadline_notes = 'Frist vom Gericht in der prozessleitenden Verfügung bestimmt (§ 273 ZPO, prozessuale Förderungspflicht § 282 ZPO). In der Praxis ca. 4 Wochen ab Zustellung der Klageerwiderung; mit "Datum setzen" überschreiben, sobald die gerichtliche Verfügung vorliegt.',
+    deadline_notes_en = 'Period set by the court in its case-management order (§ 273 ZPO; parties'' duty to file timely under § 282 ZPO). Typically ca. 4 weeks after service of the Statement of Defence; use "Set date" to override once the court issues the actual period.'
+WHERE submission_code = 'de.inf.lg.replik'
+  AND is_active = true
+  AND parent_id IS NULL;
+
+-- Duplik anchors on Replik (de.inf.lg.replik).
+-- Guard: parent_id IS NULL — only fires against the pre-fix shape.
+UPDATE paliad.deadline_rules
+SET parent_id = (
+        SELECT id FROM paliad.deadline_rules
+        WHERE submission_code = 'de.inf.lg.replik'
+          AND is_active = true
+        LIMIT 1
+    ),
+    is_court_set   = true,
+    legal_source   = 'DE.ZPO.273',
+    deadline_notes = 'Frist vom Gericht in der prozessleitenden Verfügung bestimmt (§ 273 ZPO, prozessuale Förderungspflicht § 282 ZPO). In der Praxis ca. 4 Wochen ab Zustellung der Replik; mit "Datum setzen" überschreiben, sobald die gerichtliche Verfügung vorliegt.',
+    deadline_notes_en = 'Period set by the court in its case-management order (§ 273 ZPO; parties'' duty to file timely under § 282 ZPO). Typically ca. 4 weeks after service of the Reply; use "Set date" to override once the court issues the actual period.'
+WHERE submission_code = 'de.inf.lg.duplik'
+  AND is_active = true
+  AND parent_id IS NULL;