refactor(env): template environment.d config and update fish aliases

Replace hardcoded config/environment.d/generic.conf with a Tera
template (environments.tmpl) rendered via mise, pulling DOTFILES_DIR,
THEME_DIR, SECOND_BRAIN, and user info from mise.toml vars.

- Add SECOND_BRAIN variable in mise.toml for the vault path
- Update fish aliases to use $SECOND_BRAIN instead of a hardcoded path
- Fix Obsidian nvim aliases with proper quoting
- Remove stale dotfiles.conf template reference

mise.toml

@@ -3,6 +3,7 @@ USER_FULLNAME = "Steve Beaulac"
 USER_EMAIL = "steve@beaulac.me"
 DOTFILES_DIR = "{{config_root}}"
 THEME_DIR = "~/.config/omarchy/current/theme"
+SECOND_BRAIN = "~/Documents/sjv-brain"
 
 [env]
 DOTFILES_DIR = "{{config_root}}"
@@ -15,9 +16,8 @@ dotfiles.default_mode = "symlink-each"
 "~/.config/btop" = "config/btop"
 "~/.config/btop/themes/current.theme" = { source = "~/.config/omarchy/current/theme/btop.theme", mode = "symlink" }
 "~/.config/emacs" = "config/emacs"
-"~/.config/environment.d" = "config/environment.d"
+"~/.config/environment.d/generic.conf" = { source = "templates/environments.tmpl", mode = "template", template = "tera" }
 "~/.gnupg" = "config/gnupg"
-"~/.config/environment.d/dotfiles.conf" = { source = "templates/dofiles.conf.tmpl", template = "tera", mode = "template" }
 "~/.config/fish" = "config/fish" # check if we really need the fisher plugins
 "~/.config/gdb" = "config/gdb" 
 "~/.config/ghostty" = "config/ghostty"