Remove --free, implement shared CPU/memory and automatic defaults

[nathanjcochran]

See Slack thread and AGE-208 for background.

This implements the changes in AGE-208, with one relatively minor difference: I did not implement explicit "auto" options for each flag. Instead, I just removed the default value for each flag, and am interpreting the zero value (i.e. when the flag is omitted) to mean "auto". This was just a little easier to implement as a first pass, as it meant that I didn't need to update as much of the --help text to include references to "auto" or explain what it means. I think it would be easy to add explicit "auto" options as a follow-up, if we're sure we want it.

This PR:

• Gets rid of the --free flag.
• Adds support for specifying shared for --cpu and --memory (this is how you create a free services now).
• Gets rid of the explicit defaults for --addons, --region, --cpu, and --memory
  • These parameters are no longer sent in the API request if they aren't specified.
  • The default values are now determined in the API layer.
  • The --cpu and --memory defaults now depend on what type of plan you're on (the free plan defaults to shared CPU/memory, whereas paid plans default to 0.5 CPU/ 2 GB.
  • The --addons and --region defaults depend on what type of service you're creating.
    • If you're creating a free service (shared CPU/memory), --addons defaults to time-series,ai, whereas if you're creating a paid service, it defaults to time-series.
    • --region currently always defaults to us-east-1, but we intend to have it intelligently choose the best region for paid services in the future.
• Makes corresponding changes to the service_create MCP tool.

How to test:

• Check out https://github.com/timescale/savannah-public/pull/51, build and run it: go install ./... && server
• Check out this branch and build it: go install ./...
• Configure your CLI to point to your local savannah-public server: tiger config set api_url http://localhost:8080/public/api/v1
• Create a service: tiger service create (default service type depends on your plan)
• Create a free service: tiger service create --cpu=shared

Related PRs:

• https://github.com/timescale/timescale-graphql-client/pull/8
• https://github.com/timescale/savannah-public/pull/51

[Askir]

generally looks good to me but could use a bit better explanation I think

[Askir]

I think this is a bit confusing with the default behavior not being mentioned?

[nathanjcochran]

I agree, but I think it's going to be hard to fit an explanation of the default behavior into the flag descriptions (whereas previously, it was easy to just list a default value). We can list auto as the default in a follow-up PR if we think that's clearer (I think that change should be backwards-compatible), but I still don't think it would really explain much.

So I think it needs to go in the main --help text. How does this look for now (at least as a first pass - can definitely improve later)? 346aae9

[Askir]

I think at least here we should document the default behavior. I'd actually prefer to have auto/auto as a specific option but even if we don't have it we should explain what not providing anything does.

[nathanjcochran]

Yeah, agree. See my other comment above.