Upgrade Terraform Sentry provider to v0.15.4

[dschaller]

Summary

• upgrade github.com/jianyuan/terraform-provider-sentry from v0.11.2 to v0.15.4
• mux the existing SDKv2 provider with the upstream Terraform Plugin Framework provider
• upgrade the Pulumi Terraform Bridge to v3.135.0 and Pulumi dependencies to v3.253.0
• expose the current SentryAlert resource and project error/issue-stream monitor lookups
• regenerate the .NET, Go, Node.js, and Python SDKs
• update the repository to Go 1.26 and golangci-lint v2

Sentry has retired the classic project issue-alert-rules API. Existing SentryIssueAlert reads now receive HTTP 410 responses. Upstream v0.15.4 includes the replacement monitor-based alert resource and marks the classic issue alert resource deprecated.

This builds on and supersedes #28. The original mux work remains in commits authored by @auvred.

Provider-defined function limitation

The new op_jsonpath and op_status_code_check Terraform functions both have a parameter named operator. Current Pulumi .NET codegen does not escape that reserved C# identifier for multi-argument provider-defined functions and emits an SDK that cannot compile. This change omits those two optional helper functions from the Pulumi schema. SentryUptimeMonitor remains available and accepts the assertion strings those helpers construct.

Java remains unchanged from main. The Java SDK added in #28 was generated with the repository pinned 0.17.0 generator, which cannot import the current parameterized provider schema.

Validation

• make test_provider
• make lint_provider.fix
• make lint_provider
• make build_dotnet
• make build_go
• make build_nodejs
• make build_python

All listed checks pass locally.