[New Feature]: Monitor and recommend localized-translation consensus for `Proprietary` manifest License

### Description of the new feature/enhancement

Many packages declare `License: Proprietary` in their en-US manifests. When contributors add a locale manifest (e.g. `*.locale.zh-CN.yaml`), they need to translate such values, but there is nither guidance nor machine-readable reference — even though each language already has a de-facto consensus translation. Today that consensus exists only implicitly across the thousands of existing locale manifests, so every contributor has to rediscover it.

We request that, such consensus should be documented as machine-readable for manifest creators such as Windows Package Manager Manifest Creator (aka winget-create) so that they can prompt contributors when they maintain these manifests.

###### Consensus by db952a8

Locale | Total | Major translation
-- | -- | --
zh-CN | 23264 | 专有软件 [x23238], 私有软件 [x1]
zh-TW | 92 | 專有軟件 [x60], 專有軟體 [x32]
zh-HK | 58 | 專有軟件 [x58]
zh-Hans / zh-Hans-CN | 23 / 23 | 专有软件 [x23]
de-DE | 143 | Proprietäre [x81], Proprietär [x60]，Geschützt [x2]
de / de-AT / de-CH | 6 / 2 / 4 | Proprietäre
pt-BR | 74 | Privativo [x71], Proprietário [x3]
pt-PT | 5 | Privativo [x5]
ru-RU | 72 | несвободные [x61], Поприетарная [x8]
fr-FR | 59 | Propriétaire [x51], Privateur [x8]
fr / fr-CH | 2 / 3 | Privateur
ja-JP | 30 | プロプライエタリなソフトウェア [x14], プロプライエタリ [x10], 非表示の出典 [x3]
ko-KR | 4 | 숨겨진 원천 [x3], 프리웨어(독점) [x1]
pl-PL | 12 | własnościowe [x12]
nb-NO | 31 | Proprietær [x27]
nl-NL | 20 | Private [x20]
es-ES | 6 | Privativo [x5], Propiedad exclusiva [x1]
it-IT | 7 | Proprietario [x7]
tr-TR | 7 | özel mülk [x5], Tescilli [x2]
uk-UA | 8 | Попрієтарна [x8]
sr-RS | 8 | Власнички [x8]
be-BY | 8 | Папрыетарная [x8]
da-DK / nb / nn-NO / sv-SE / it-CH / nl-BE / es | each 1–5 | Proprietær / Proprietär / Proprietario / Private / Privativo, etc.

### Proposed technical implementation details (optional)

_No response_

Review the existing *.locale.zh-CN.yaml manifests and the en-US manifests to understand how localized License values are represented. Then examine the Windows Package Manager Manifest Creator (winget-create) mentioned in the request; done means defining a machine-readable consensus reference and a contributor prompt, with the format and integration point agreed.

Written by the indexing model from the issue text.