ref: Update Igniter install task

[andreas-ementio]

changing the following in the installer mix task :

• update install mix task to use finch (commit 49ef2f7)
• bump installed jason dependency to ~> 1.4
• use config_env() in generated prod.exs
• only add Sentry.PlugCapture when the project uses Cowboy

[sentry]

Bug: The has_dep?(:plug_cowboy) check reads from the on-disk mix.exs, not in-memory state. If sentry.install is composed after add_dep without applying changes, the check will fail.
_{Severity: LOW}

Suggested Fix

The has_dep? check should be made aware of pending changes in the igniter state. Alternatively, if this composition pattern is unsupported, the documentation for Igniter should be updated to clarify that changes must be applied before running dependent tasks.

Prompt for AI Agent

Review the code at the location below. A potential bug has been identified by an AI
agent. Verify if this is a real issue. If it is, propose a fix; if not, explain why it's
not valid.

Location: lib/mix/tasks/sentry.install.ex#L141

Potential issue: The `sentry.install` task uses
`Igniter.Project.Deps.has_dep?(:plug_cowboy)` to decide whether to add
`Sentry.PlugCapture`. This function checks the on-disk `mix.exs` file, not the in-memory
state of an `igniter` process. If a developer programmatically composes tasks by first
adding `:plug_cowboy` with `add_dep` and then immediately running `sentry.install`
without first applying the changes to disk, the check will incorrectly return `false`.
This results in `Sentry.PlugCapture` being omitted from the configuration, even though
the project will have the `:plug_cowboy` dependency.

_{Did we get this right? 👍 / 👎 to inform future reviews.}