memory: reconcile timer memories with Syncro add_line_item switch

Mike's overhaul replaced the timer workflow with add_line_item, and he
already rewrote feedback_syncro_timer_first.md. Reconcile the leftovers:
- MEMORY.md index line for timer_first still stated the superseded
  "timers required" rule as current — rewrite to the add_line_item rule.
- timer_entry response-shape memory is now about a dead workflow — mark
  it HISTORICAL (index + file banner), retained only for manual timer use.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

.claude/memory/MEMORY.md

@@ -37,8 +37,8 @@
 - [Syncro — leave contact blank by default](feedback_syncro_blank_contact.md) — Default to blank contact ("Not Assigned") on tickets and billing for ALL customers. Blank lets Syncro use company-level email defaults; setting a contact may route to a secondary email and bypass distribution. Generalizes the prior Cascades-only rule per Winter 2026-05-04.
 - [Syncro — never set contact on Cascades tickets](feedback_syncro_cascades_contact.md) — Cascades-specific instance of the blank-contact rule above. Kept for the Meredith-defaulting incident detail.
 - [Syncro — use a billable labor type, never "Prepaid project labor"](feedback_syncro_labor_type.md) — Time entries must use in-shop / onsite / remote / web labor. "Prepaid project labor" is exempt and won't decrement prepay blocks. Default is Remote labor for typical support tickets. Winter caught this 2026-05-04.
-- [Syncro — log time entries first, never bare add_line_item](feedback_syncro_timer_first.md) — All Syncro work-time billing MUST go through `timer_entry → charge_timer_entry`. Bare `add_line_item` leaves Syncro time tracking at 00:00:00 and breaks reporting. Mike caught this on 2026-04-30 across 31 tickets; I repeated the bug on 2026-05-01 across 3 more.
-- [Syncro — timer_entry response is FLAT](feedback_syncro_timer_response_shape.md) — POST /tickets/{id}/timer_entry returns `{"id": N, ...}` directly, NOT `{"timer": {...}}`. Parse as `.id`. The skill doc's `.timer.id // .timer_entry.id` fallback always resolves to null and causes duplicate-timer retries. Hit on #32253 2026-05-05.
+- [Syncro — bill with add_line_item, not timers](feedback_syncro_timer_first.md) — Bill tickets with `POST /tickets/{id}/add_line_item` directly; the timer workflow (`timer_entry → charge_timer_entry`) is NOT used. Set product_id, quantity (decimal hours), price_retail, name, description, taxable:false. Supersedes the old "timers required" rule (Mike confirmed 2026-05-21).
+- [Syncro — timer_entry response is FLAT (HISTORICAL)](feedback_syncro_timer_response_shape.md) — Reference only: timers are NO LONGER part of the billing workflow (superseded by add_line_item — see feedback_syncro_timer_first.md). Retained for the rare manual-timer case: response is flat (`{"id": N, ...}`), parse `.id` not `.timer.id`. Originally hit on #32253 2026-05-05.
 - [Syncro — warranty has its own product, never patch dollar amounts](feedback_syncro_warranty_product.md) — Warranty/no-charge work uses product `1049360` (Labor- Warranty work, $0). Do NOT use Remote/Onsite + `billable: false` — Syncro silently overrides the flag. Do NOT patch `price_retail` to convert one labor product into another; pick the correct product and re-run. Hit on #32225 2026-05-06.
 - [SQL instance role — verify by connections, not name](feedback_sql_instance_role_by_connection.md) — Standard installed under default `SQLEXPRESS` instance name is real. Prove role with `sys.dm_exec_sessions` + `Get-NetTCPConnection -OwningProcess` before recommending stop/uninstall. IMC1 2026-05-05/06 near-miss.
 - [Syncro — confirm appointment owner explicitly](feedback_syncro_appointment_owner.md) — When creating tickets with appointments, always ask "who is the appointment owner?" in the preview. Don't auto-default to ticket's assigned tech. Don't add additional attendees without explicit confirmation. Howard caught on Kittle ticket #32263 2026-05-08.

.claude/memory/feedback_syncro_timer_response_shape.md

@@ -4,6 +4,10 @@ description: POST /tickets/{id}/timer_entry returns a flat object {"id": N, "tic
 type: feedback
 ---
 
+> **SUPERSEDED / HISTORICAL — 2026-05-21.** Timers are no longer part of the ACG Syncro
+> billing workflow; billing uses `add_line_item` directly. See [[Syncro — use add_line_item for billing, not timers]] (`feedback_syncro_timer_first.md`). Keep this note ONLY as reference
+> for the rare case a timer is created manually — do not treat it as current workflow.
+
 **Rule:** When parsing the response from `POST /tickets/{id}/timer_entry`, use `.id` directly — the response is a FLAT object. Do NOT use `.timer.id // .timer_entry.id`.
 
 **Verified response shape (2026-05-05, ticket #32253):**