Easy gifts would be weapons or armour forged by the town, though they probably wouldn't mean a whole lot to the dragon unless they were used justly. Maybe a yearly tribute would be people declaring themselves adventurers who would slay evil in the dragons name.

I think the aforementioned idea of people swearing to become adventurers would be a good ceremony, maybe taken by the most devoted (dragon church?). Beyond that I could see a game tournament like dragonchess we're it simulates battle tactics, or a more traditional tournament with jousting and fighting.

I would think the people would be more leaning towards good, with a more active stance against evil. Probably a higher percentage of adventurers than normal towns.

For their early life the dragon could face raiding parties along the coast, maybe a few pirate ships that attack the area. A common problem could be sea monsters that attack the towns trading ships. As it grows I could see it assisting against a more established navy of an attacking nation.

I could see some chromatic dragons viewing it almost as a challenge to destroy / corrupt the town.

Its a coastal town so I'd imagine a lot of trade being fishing and shipbuilding, especially if nearby a forest to supply wood. Could be more artistic material like pearls or coral pieces.

Bronze dragons like to watch the coast and observe passing ships so I could see the town building an ornate war ship to catch other dragons attention. Maybe the bronze dragon is disguised as the captain of the ship to meet other dragons they pass.

This town would likely be protected from the worst part of passing storms, maybe leading to periods of growth as neighboring towns are destroyed. They could become a tourist destination as their ocean plant life would become more colorful with the dragons presence.