GeezerVison

Switching vaults during a snippet search retained the query and pre-search selection. Clearing the query could restore a snippet or folder from the previous vault. Reset snippet search state when the Code space is reset, and also discard the HTTP pre-search selection snapshot during its existing search reset.

Audited the remaining search entry points: Notes was fixed in #939; Math, Drawings, editor content search, and local HTTP filters are component-local and unmount when navigating to vault settings; the command palette clears its search on close.

Validation: 35 targeted tests passed across snippet search, Code initialization, HTTP search/initialization, and Notes search/initialization. Scoped ESLint passed. Added regressions covering vault changes and subsequent search restoration. No manual application UI verification.