[deckhouse-cli] mirror: support multiple version constraints for the same module/package

[ldmonster]

Currently repeating a module or package name in a filter expression (e.g. --include-module foo@=v1.0.0 --include-module foo@=v1.1.0) errors out or silently drops all but the last declaration. This change makes it possible to pin multiple versions of the same name in a single mirror pull invocation.

What changed

• Added MultiConstraint — an OR-combination of constraints for the same name. It is produced automatically when a name is repeated on the command line and is transparent to all existing code paths.
• Replaced the "module redeclared" error in NewFilter with mergeConstraints, which folds repeated declarations into a MultiConstraint.
• Added ExactConstraintsOf and SemverConstraintsOf helpers that flatten a MultiConstraint into typed slices, used by applyChannelAliases and the proxy-registry probe path respectively.
• VersionsToMirror now recursively resolves MultiConstraint sub-constraints and deduplicates the resulting tag list so overlapping ranges don't cause redundant pulls.
• applyChannelAliases (modules and packages) now iterates over all pinned tags. The historical behaviour — a single pinned tag without an explicit +channel suffix is propagated to every release channel — is preserved only when exactly one version is pinned; when several are pinned simultaneously each one is aliased only to its own explicitly named channel (if any) to avoid them overwriting one another.
• probeModuleTags / probePackageTags now iterate over every semver sub-constraint so proxy-registry probing works correctly with a MultiConstraint.
• Added listAllVersionTags to package mirroring so vX.Y.Z-only tags (e.g. dev packages that publish no release channels) are discovered and cloned even when they wouldn't be reached by channel-based discovery.

Example

d8 mirror pull \
  --include-package myapp@=v1.2.0 \
  --include-package myapp@=v1.3.0 \
  ...

Both v1.2.0 and v1.3.0 are now pulled instead of only the last declaration winning.