P3: depreciation straight-line by days through the final month, schedules by day (defects 22, 9, D-37)

The final month takes what the months before leave, spread over its days;
a disposed asset stops on its disposal day. A skipped month is caught up
in the month the run is made; a reversed run un-posts its month. New
schedules spread by day; equal-months schedules must start on the 1st.
Amounts round to the currency's own minor unit. Kani and Lean proofs; an
exhaustive search over runs, reversals and disposals.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01T3gXMVt7XJPi6ens1or9Dj

examples/schedule-daily-deferred-revenue.toml

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+id = "schedule-daily-deferred-revenue"
+title = "Deferred revenue is earned by the day, to the cent"
+rule = "Revenue collected in advance for a service over time is recognized as each day of the service passes, one posting per calendar month, the last month taking what the others leave."
+status = "CHOICE"
+sources = ["ASC 606-10-25-23", "DECISION: plan/served.md D-11, D-37 (owner, 2026-10-20)"]
+tags = ["schedules", "deferred-revenue", "daily", "p3-defect-9"]
+
+[setup]
+currency = "USD"
+fiscal_year_start = "01-01"
+basis = "accrual"
+rounding = "half-away-from-zero"
+
+[[setup.accounts]]
+code = "1000"
+name = "Bank"
+type = "asset"
+
+[[setup.accounts]]
+code = "2400"
+name = "Deferred Revenue"
+type = "liability"
+
+[[setup.accounts]]
+code = "4000"
+name = "Subscription Revenue"
+type = "revenue"
+
+# 1,000.00 collected for service 2026-01-05 through 2026-04-04.
+[[setup.schedules]]
+id = "SUB"
+kind = "deferred_revenue"
+description = "Quarterly plan, a customer"
+total = "1000.00"
+start = "2026-01-05"
+months = 3
+convention = "daily"
+balance_account = "2400"
+pl_account = "4000"
+
+[[events]]
+date = "2026-01-05"
+description = "Collected a quarter up front"
+lines = [
+  { account = "1000", side = "debit", amount = "1000.00" },
+  { account = "2400", side = "credit", amount = "1000.00" },
+]
+
+[[events]]
+run_schedules = { through = "2026-04-30" }
+
+# Hand check (worked without the code): January holds 27 of its 31 days
+# (5-31); February and March are whole; April holds days 1-4 and takes the
+# rest. Cumulative at each month end: 1,000 x (27/31)/3 = 290.3226 ->
+# 290.32; 1,000 x (27/31 + 1)/3 = 623.6559 -> 623.66; 1,000 x (27/31 +
+# 2)/3 = 956.9892 -> 956.99; then 1,000.00. Months: 290.32, 333.34,
+# 333.33, 43.01.
+[[expect]]
+query = "schedule_plan"
+schedule = "SUB"
+
+[expect.values]
+"2026-01-31" = "290.32"
+"2026-02-28" = "333.34"
+"2026-03-31" = "333.33"
+"2026-04-30" = "43.01"
+
+# Earned through March: 956.99; still owed for April 1-4: 43.01.
+[[expect]]
+query = "balances"
+as_of = "2026-03-31"
+
+[expect.values]
+"2400" = "43.01"
+"4000" = "956.99"