feat(iace): FMEA P1 — open methodology anchors + bp_iace_fmea_kb

P1 of the auto-FMEA build plan: establish the public-domain methodology
foundation (no AIAG-VDA/SAE/IEC tables reproduced).
- fmea_data_sources.go: MIL-STD-882E severity (Cat I-IV→1-10) + probability
  (A-F→1-10 with per-hour λ bands), OccurrenceFromRate(λp·α), SeverityForCategory,
  MIL-STD-1629A CriticalityCm = λp·α·β·t. Own 1-10 projection, government-anchored.
- 4 versioned source docs (MIL-STD-1629A, MIL-STD-882E, NASA RCM, FMD-91/NPRD-91)
  ingested into the new RAG collection bp_iace_fmea_kb (whitelisted).
- Tests for all scales/mappings/criticality (green).

Next (P1 step 2): fetch FMD-91/NPRD-91 bulk λ/α tables from DTIC.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
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# Severity & probability scales — MIL-STD-882E (US public domain)
Open S/O anchor for the IACE auto-FMEA. The 110 projection used in code is
BreakPilot's own; these public-domain categories provide the defensible anchor
(no copyrighted AIAG-VDA/SAE 110 table is used). Ingested into `bp_iace_fmea_kb`.
## Source
- **Source:** US DoD — MIL-STD-882E, *System Safety* (Distribution Statement A, approved for public release)
- **License:** US Government work — **public domain**
- **Attribution:** `Source: MIL-STD-882E (US DoD), public domain`
- **Retrieved:** 2026-06 · **Ref:** DLA QuickSearch (ident 36027)
## Table I — Severity (→ our 110 S)
| Cat | Severity | Threshold | our S |
|---|---|---|---|
| I | Catastrophic | Death, permanent total disability, irreversible severe environmental damage | 10 |
| II | Critical | Permanent partial disability; hospitalisation of multiple persons | 7 |
| III | Marginal | Injury/illness with lost work day(s) | 4 |
| IV | Negligible | Minor injury, no lost work day | 2 |
## Table II — Probability (individual item) (→ our 110 O)
| Lvl | Name | Qualitative | rate band (/h, our calibration) | our O |
|---|---|---|---|---|
| A | Frequent | likely to occur often | ≥ 1e-1 | 10 |
| B | Probable | will occur several times | 1e-2 … 1e-1 | 8 |
| C | Occasional | likely to occur sometime | 1e-3 … 1e-2 | 6 |
| D | Remote | unlikely but possible | 1e-6 … 1e-3 | 4 |
| E | Improbable | so unlikely ~ may not occur | < 1e-6 | 2 |
| F | Eliminated | incapable of occurrence | 0 | 1 |
## Detection (no government scale)
Detection is an AIAG/SAE concept with no public-domain table. IACE defines its
OWN 110 detection scale grounded on the generic **diagnostic-coverage** concept
(1 = built-in diagnostic always catches it … 10 = latent, no detection). The
IEC-61508/13849 DC tables are copyrighted and are NOT reproduced — only the
concept (in our own words) is used.
## How used in IACE
`MILStd882Severity` / `MILStd882Probability` / `OccurrenceFromRate` /
`SeverityForCategory` in fmea_data_sources.go implement these bands. Severity is
preferably resolved through the linked ISO 12100 hazard; occurrence from λp·α.