Normalize frontmatter taxonomy across 293 document transcriptions

Categories now match folder names (15 canonical values).
Types normalized to 25 canonical values per VAULT_MAP.md spec.
Context-aware mapping: W-2s→tax-form, lease files→lease, vet records→vet, etc.

documents/argo/2018-01-20 North Austin - Vaccines.md

@@ -1,6 +1,6 @@
 ---
 date: 2018-01-20
-type: invoice
+type: vet
 provider: North Austin Animal Hospital
 location: Austin, TX
 total: $154.00

documents/argo/2018-04-20 Austin Vet Care - Wound Treatment.md

@@ -1,6 +1,6 @@
 ---
 date: 2018-04-20
-type: invoice
+type: vet
 provider: Austin Vet Care @ Central Park
 location: Austin, TX
 total: $446.30

documents/argo/2018-12-27 North Austin - Vaccines.md

@@ -1,6 +1,6 @@
 ---
 date: 2018-12-27
-type: invoice
+type: vet
 provider: North Austin Animal Hospital
 location: Austin, TX
 total: $132.00

documents/argo/2019-12-04 Sunnyvale Vet - Annual Exam.md

@@ -1,6 +1,6 @@
 ---
 date: 2019-12-04
-type: invoice
+type: vet
 provider: Sunnyvale Vet Clinic
 location: Sunnyvale, CA
 total: $306.00

documents/argo/2021-11-08 VCA West LA - Emergency Visit.md

@@ -1,6 +1,6 @@
 ---
 date: 2021-11-08
-type: medical-record
+type: vet
 provider: VCA West Los Angeles Animal Hospital
 location: Los Angeles, CA
 total: $495.80

documents/argo/2021-11-24 VCA Brentwood - Well Patient Exam.md

@@ -1,6 +1,6 @@
 ---
 date: 2021-11-24
-type: invoice
+type: vet
 provider: VCA Brentwood Animal Hospital
 location: West Los Angeles, CA
 total: $189.35