New-JiraIssue and Set-JiraIssue should use CreateMeta and EditMeta API endpoints for issue/field schematic info

[hmmwhatsthisdo]

Context

Is your feature request related to a problem? Please describe.

Currently, Jira supports defining multiple custom fields with the same (user-visible) name. When querying Jira's fields API, it's impossible to know which instance of a duplicate-name field corresponds to the user's intended field selection.

Jira's CreateMeta and EditMeta endpoints are scoped to individual projects/issue[type]s and clearly indicate which fields are available in a given context. These endpoints mean there's no chance for duplicate-name fields to introduce ambiguity.

Description

Describe the solution you'd like

Replace calls to Get-JiraField with data from calls to Get-JiraIssueCreateMetadata (already present) or Get-JiraIssueEditMetaData

Additional Information

New-JiraIssue already calls Get-JiraIssueCreateMetadata, but only uses the information from this call for asserting required fields. We could build upon this to also extract the ID <-> Name map of available fields instead of calling Get-JiraField (or at least try using the *Meta endpoints before falling back)