fix(test): call configure() on script addons in taddons.context.configure - #8369

Summary

context.script() returns an addon that is register()-ed but never added to AddonManager.chain. The options.changed -> _configure_all -> trigger() broadcast that normally calls configure() after an option change only walks self.chain, so a script addon's configure() is silently never called again after the initial load — even though context.configure(addon, some_option=...) updates the option value itself just fine. This makes it impossible to write a test that exercises a script addon's configure() reaction to an option change.

Reproduced on current main with a minimal script addon that records its configure() calls: after tctx.configure(addon, foo='bar'), the option updates but configure() is never invoked a second time.

Changes

• mitmproxy/test/taddons.py: context.configure() now explicitly invokes ConfigureHook on the target addon after updating options, but only when that addon isn't already part of self.master.addons.chain — chained addons (the common case, e.g. context(some_addon)) already receive the hook via the existing options.changed broadcast, so this avoids calling configure() twice for them.
• test/mitmproxy/data/addonscripts/configure_recorder.py: new fixture script addon that records every updated set passed to its configure().
• test/mitmproxy/test_taddons.py: regression test loading the fixture via context.script() and asserting configure() is called with the changed option key after context.configure(). Verified the test fails on unpatched taddons.py and passes with the fix.

Fixes #3402