fix: replace deprecated catch_stack with current_exceptions

[PranavGadge01]

Problem

The plugin imports and calls Base.catch_stack in 3 places.
This function is deprecated in Julia and lives in deprecated.jl,
as confirmed by:

@doc Base.catch_stack
# [1] catch_stack(; ...) @ deprecated.jl:213
# [2] catch_stack(task; include_bt) @ deprecated.jl:213

When Julia fully removes it in a future version, the plugin
will crash on startup for every user.

Fix

Replace all 3 usages of catch_stack() with current_exceptions(),
which is the official modern replacement:

• Remove catch_stack from the import Base: line
• Replace catch_stack() with current_exceptions() in the
  error handling block
• Replace catch_stack() with current_exceptions() in the
  display error fallback

Verification

Running @doc Base.catch_stack in a Julia 1.12 session confirms
both methods are defined in deprecated.jl:213, meaning Julia
has officially marked this function for removal.

[PranavGadge01]

@hammerfunctor could u please check...