tgc-revival: Refactor FindIdentityParams to use multi-segment logical AND matching

[zli82016]

Previously, the FindIdentityParams function within the TGC generator attempted to identify a single uniquely distinguishing URL path segment (IdentityParam) to differentiate between Terraform resources that share the exact same CAI asset type.

However, this naive approach fails on complex resource groupings like compute.googleapis.com/FirewallPolicy, where resources like NetworkFirewallPolicy and RegionNetworkFirewallPolicy share parameters globally and regionally, meaning they require a combination of path segments (e.g., "projects" AND "global") to be reliably identified.

This PR completely refactors the identity parsing logic to aggressively group all identifying segments together rather than isolating just one.

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[modular-magician]

Hi there, I'm the Modular magician. I've detected the following information about your changes:

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terraform-google-conversion: Diff ( 1 file changed, 26 insertions(+), 26 deletions(-))

[modular-magician]

Hi there, I'm the Modular magician. I've detected the following information about your changes:

Diff report

Your PR generated some diffs in downstreams - here they are.

terraform-google-conversion: Diff ( 1 file changed, 26 insertions(+), 26 deletions(-))

[modular-magician]

Hi there, I'm the Modular magician. I've detected the following information about your changes:

Diff report

Your PR generated some diffs in downstreams - here they are.

terraform-google-conversion: Diff ( 1 file changed, 26 insertions(+), 26 deletions(-))

[zli82016]

/gcbrun